British Nuclear Deterrent – A move to air launched?

I saw that this has been suggested as a possible way of Britain retaining its nuclear weapons, so it got me thinking.

Air Delivered Deterrent
Pro – (Arguably) cheaper, can be used tactically.
Con – Least survivable option, required dedicated strategic bomber force to remain a credible strategic deterrent.

Other than Tornados which were formerly used for UK nuclear weapons, the RAF has no suitable delivery aircraft, so a large investment in a new bomber force would be needed, but would probably still be cheaper than Trident.

SLBM
Pro – Considered highly survivable, strategic capability
Con – Expensive, an ‘all eggs in one basket’ risk.

It’s what we have at the moment, but relies on a single submarine at any one time and is higly expensive.

ICBM
Pro – Cheaper than SLBM by a long margin, strategic reach
Con – Not as survivable as a submarine

At $7million each they aren’t cheap, but buy a large lot of Minutemen ICBMs from the USA and building some Silos is likely to be cheaper than the £30billion to replace trident, and maintains a good deterrent.

Cruise Missile
Pro – Cheap, can be land, sea or air based
Con – Comparatively short range

Could be an option, so long as the threat isn’t from too far away

No Deterrent
Pro – Saves money
Con – No deterrent in an unpredictable world with ever increasing nuclear proliferation.

Relies on US or France to shield us from nuclear attack and puts us in a much more vulnerable position generally.

I’m sure you can tell that I am very much pro-deterrent, and from my armchair analysis it seems that an ICBM might be a good compromise that would preserve most of our capability at a much reduced cost.

If the UK does decide to switch to air launched deterrent, what are the options?

Rafale? 2018 bomber? Nuclear UCAV?