It's 2 very different things.
When signing up for the regular RAF you're not just getting a job, you're getting a life, in the Forces, with all the pros and cons that come with that. Aptitude is only one part of the package and a high aptitude is no guarantee of anything. And you don't necessarily qualify for "most things", different trades and branches require different aptitudes. The skills that make you score high in one are not necessarily the same as the skills that help you score highly in another. You may score highly for Int, but that doesn't mean you'll score highly for ABM, for instance.
Presumably you were going for the Reserves because you've got a job and a life on the outside that you like/enjoy and want to keep. By going regular you're stopping all that, even your social life and, to some extent, your friends. You're at the beck and call of the military 24/7 then, it's not just one night a week, one weekend a month and an exercise week every now and then, it's full time and permanent.
Yes, you can do degrees in service, but it is by far the hardest way round of doing them. Again remember this isn't a typical 9-5 job that gives you masses of free time to complete a degree at your leisure, it's the modern (stretched) armed forces.
As for are other opportunities available to you... well, yes, but they come at the cost of not being 'free' to be a civilian on your down time.
It really comes down to what you want. What was the reason you applied for the reserves in the first place?