I agree that there are a lot more things for the GM to deal with in a space game and you are right as the PC's can more far and fast if they want to. And essentially generating whole new worlds, world maps, societies, etc is a huge pain that is only a small part of a fantasy game.
IMO I just think that the skill category and skill method is easier to add skills to than tacking it on in RMC/2/X. In RM2/C/X you have to decide if it gets a level bonus, what to price it at and if everyone can learn it or is it a special skill just for a single profession or maybe a small group of professions.
I was also thinking that some people like talking about RM and then Advanced RM. IMO RMSS style would work great for those who do not like expanded skill sets. Also in larger skill sets you generally need a different way to organize them do to their size.
For Example:
In my new space game I have approx. 641 lines in Excel that represent Skill Categories and skills them selves. That is a lot more then in RMC/2, it also includes the new Psi system of SM:P in which each power is a skill under a skill category so that is partially why it is bigger. There are also some spaces just for ease of reading that add to the blot but that may just trim it by 20%. There are also all the skills from RMSS, RMSS Black OP's as well as some from the various RMSS Comp and some skills from the RM2 Elemental Comp.
Anyway the sheer size of it would be vastly harder to work with in a RMC/2 system, where as here you just decide on the skill category, skill type [E,O,R] and you are done. The profession bonus is already added to the skill category if needed, you can add a skill in the middle of the game with only a few pencil strokes and it can mesh with the spells in SL and the Companions well if it is a category that is specified in the spells description.
Anyway I was just seeking others opinion on the skill system question to get some posts going.
Please keep commenting as I am curious to what you have to say no matter what system you are using, or have used in the past or present.
MDC