I especially like the idea of letting the player decide his space program's financial model.
Specializing in any of those will require a big investment of science and money (for unlocking parts), so at first, you have to make some choices on what you prefer to do with your playthrough. Of course, after a while, you should be able to unlock everything anyway.
I'd also suggest having multiple different reputation bars, one to do with each area of expertise (an agency for example can have very poor reputation with satellites but a high reputation for space tourism)
Space Tourism:
Includes an extended "Tourism" tech line with all manner of 'comfort' rocket/plane parts.
As your reputation grows, it becomes necessary to unlock those and create rockets that can take more kerbals to more exotic destinations more comfortably, as it becomes more difficult to make money by doing low-profile tours (your facilities cost more to maintain already, your experienced staff require bigger salaries not to move to competing agencies)
Space Settlement:
A focus on off-kerbin bases. A tech tree line to match. Specializing in, of course, creating larger, more comfortable and long-lasting residences in space! Luxury orbital space stations with all the amenities and space restaurants and planetside colonies.
Ties in to space tourism to an extent, as some tourists might want to relocate to minmus permanently, but you need the kind of facilities that can maintain life there for a year (comfort level requirements vary).
etc
With this, the player should have the option of seriously taking his time and, for example, just doing airplane flights of kerbin for a while for money. Just build a luxury airplane company for a while, enjoy the sights, fly around... Whatever a person wants to do.