There are at least three options for multi-role aircraft TODAY.
Firstly, we could simply buy/lease some AV-8B Harrier IIs from the Yanks, the USMC being committed to using theirs until 2030. Secondly, we could fit an arrestor system and fly a number of current jets off the ski-ramp using rocket-assisted take-off packs, leased F/A-18s being one option, and that does not require a steam generating capability. As I understand it, USAF F-16s also have hooks for emergency landing use, and I'm pretty sure the Norwegians use RATO packs for getting their F-16s off very short runways. I'm sure the US has a few we could lease. The third option is simply RAF MQ-9 Reaper drones, which can fulfill most of the Third World combat scenarios, with the added bonuses of not risking aircrew and allowing us to carry much more than 40-odd. A mix of Reapers and RATO-equipped Typhoons would seem to cover most requirements.