Only an UAV can be made with so small RCS that it is even worth trying,

That so small UAV will not be usefull either. modern radars of ships suppose to track stealth subsonic missiles. Any noisy turbo prop UAV is not worth trying.

and sending in a manned a/c to do it ? well, perhaps ask some old Japanese Kamikaze pilots then.

Those days are gone. Size and speed of aircraft carrier hasnt change much compared to WW11 but enormous improvement has been done in Airpower and continue to done. There is simply not enough money on carriers alone.

They also have enough endurance to make the info useful

That endurance comes at expense of speed and payload. it is very low subsonic like chopper.

The reasons are numerous and quite complex actually, firstly recent sanctions put in by Russians against Iran counts out a purchase now anyway.

In the past the reasons were down to:

Lack of satisfaction with Russian types already in the fleet.
Lack of technology transfer in comparison to the days of being a US client state.

What people don’t realise is during the days of the Shah the technology transfer offered to Iran by America was significant. As part of the defence contracts set up around the F14 and other types like helicopters included massive technology transfer. The US had to set up in effect manufacturer level overhaul facilities in Iran, that is one of the main reasons they have been able to keep their large but elderly US fleet going. Russia is not prepared to offer anywhere near that kind of ToT.

Another issue is a general distrust of the Air Force by the high ups in the regieme which has led to a lack of funding for new procurement.

Finally is bangs for bucks against strategic goals…to put together an airforce with equipment that is credible against its neighbours would be an expensive exercise and probably futile. On the other hand investing in IRBM, anti ship missiles and asymetric technologies like cyber warfare are far more effective in meeting their strategic goals and maintaining a deterrence against attacks.

Russia is much more generous in transferring technology & overhauls. otherwise how Iran can maintain Su-24MK/MIG-29 with related missile. Missiles like R-73 have shelf life. and RD-33 earlier versions is not known for long life.
http://www.uskowioniran.com/2011/09/fadaeeyan-e-harim-e-vellayat-iii-5.html

answer is much simpler than that. Generations of officers in Russian foreign and defence have pro-arab views from 1950s. and this limit cooperation with iran. and Iran may not have that much competent people left to absorb technology of modern Flanker.

French public debt is 86% of GDP.
British public debt is 64% of GDP.

French debt is higher in absolute terms, as well as relative to the economy. It’s about £1.4 trillion. :p

French banking system has $1T exposure to countries that may not likely to pay without further bailout . so some day this debt will come on French tax payers. UK is not that much better but France is facing almost daily downgrades of its banks.

http://www.ft.com/intl/cms/s/0/9d499486-4675-11e1-89a8-00144feabdc0.html?ftcamp=rss#axzz1kUicNBDm

what can China do if France sells Rafale to Taiwan?.
Stop buying Airbus? Stop buying Nissan? Above all not deal with Snecma-GE (C919 engine) or Turbomeca engines. Part of West strength or some cases weakness is most complex products are spread across countries.

No worries Brazil got the world cup not Russia, no whatifs there.
Brazil’s GDP growth rate is 7.5%, far higher than Russia’s at 4.9%. it doesn’t rely solely on service industries either.. plenty of raw resources to fall back on. It also has a growing population compared to Russia’s shrinking one, far more sources of labor.

both got world cup. one lacks the money to do the proper infrastructure on time. not spread out money over several years.
The same problem is happening with Canada. It simply lacks the money & skilled people to do even the necessary let alone the unnecessary like building Military-industrial complex with deep scientific research that will ultimately flow through to civilian industries. like building future long haul airliner.

http://www.thestar.com/news/world/article/1105612–canada-well-behind-russia-in-race-to-claim-arctic-seaways-and-territory

and when the Su-34 becomes fully developed and enters in numbers, the Su-25 will become more obsolete, with UCAVs coming in to complement the Su-34 to do roles that require more endurance, or at risk of high human casualty

Su-25 is not going to obsolete. It is low G bomber. It will have practically long life. as long as it is upgraded and maintained.
casually happens when high end Strike Fighters (they provide elint, sar, moving target indicators) & cruise missiles dont do full suppression of air defenses.

true, Russia also has concerns over zwiley Ukranians, Chinese illegal immigrants, and Turkish real-estate agents, but you do not need a Su-25 for those. or at least not yet.

I didnot mention Su-25 is needed for that purpose. Su-25 is used to drop even cheaper bombs. Not some specially developed PGMs for UCAVs. UAV and helicopter UAV are for survellence. moving from UAV to UCAV is very expensive. and unlikely to be replacement for Su-25.

EJ-200 hasnt been used in single engine fighter application. and it produces 20,000 thrust. not enough for heavier Gripen-NG.

M-346 is choice of IDF but Korea is dangling some future contracts. These kind of tactics works in countries like Israel that are short of funds and always looking for contracts for it companies but it will not work in countries like China/ Saudi/Russia. when there is abundance of money.
The thing that Israel produce like UAV/radars are cheaper than those produced by US/EU. so it is not that Korea is doing any favor to them.

I don’t understand the need to modify 60 aircraft over 8 years, when the Pak-Fa will be flying in numbers by then. Spend the money on Pak-Fa’s and a future interceptor in say 2025. Does the russian airforce think that the modifications would suite a threat scenario that still makes them viable in 20 years time. Once you have modified a interceptor like the MIG-31 and most of that happens in 2015-20, those planes have to be still flying in 2030.
Have the radars on the MIG-31’s been updated significantly to handle stealth aircraft trying to enter Russian air space, what about the fact that the MIG-31 would stand out in such an environment. Or are the Russian relying on pure speed, kinematics, radar power and some stealth coating materials to solve these issues. By 2030 alot of countires including China will have a reasonable number of stealth aircraft in there mix.
Russia should now start looking at a 5th to 6th generation interceptor if not only on paper to start with and have a version flying say in 2020-2025.
Also some articles i have read indicate the MIG_31 is a very hard plane to fly, requires excellent pilot skills.
Hope all the money is worth the slow effort, 20 planes a year would be more advisable

It seems Russian dont believe on so much Stealth.
Next generation ground based radars, awacs, satellites and ship borne radars in about 10 to 20 years time will be powerfull enough to locate stealth fighers more effectively at much larger distances. with advanced interlinking of networks. so it may not be necessary for MIG-31 radar to find Stealth aircraft at further ranges.
use of MIG-31 against the support assets of tankers & awacs. can decrease the scope of radius for stealth fighters.
60 planes are not big number but they are big number in context of two to three simulatneous operations.
Stealth fighers are slow, overweight and does not carry that much internally. what can J-20 or F-35 achieve by 2020 in quantity and range of AAMs? At most Meteor calibre AAM.