Skirting the edge of this topic, the way things are going the UK is not going to have any RN amphibious lift capability for much longer relying on the Aux (Bay class) and chartered vessels (Ro-Ro) to move heavy equipment. It will retain a vertical lift capability through the CVFs but amphibious raiding and other landing ops will be a thing of the past.

Basically the RM will become another elite Light Infantry force who together with the paras and SF will be the UKs fire brigades for land ops. Their support units, Artillery , Engineers, etc will be amalgamated into single units to support both and they will share equipment like the vikings (The Broncos or whatever the ATVs the Army bought will be phased out when we leave Afghanistan). The RM will maintain ship board detachments together with SF allowing them to maintain a certain uniqueness but this will be a secondry roll.