Seamless planetary landings is already possible in the game, we are just prevented from doing it by "invisible walls", because the surface collision and PG detail hasn't been cranked up in the version we are playing. In Beta 3 I went down to a moon's surface (in supercruise and normal flight) and it only needs ground collision and height mapping (easily achieved with techniques such as Perlin noise) to transform the already pretty screenshot below into something spectacular:
Of course what you do when you're down there is a different matter, but even with the current mechanics there's much that could be implemented with a little imagination and not a huge development budget such as:
Moon bases, outposts, which you can interact with in the same way as space stations - maybe not as "exciting" as we already have that functionality, but even "trivial" stuff like weather could make that more interesting.
Floating bases on water worlds could be pretty cool and would be essentially space-stations on the water, especially when you consider wave sizes are largely dictated by gravity (and wind speed) - waves on an ocean on Mars for example would be huge compared to earth. Try landing on a floating platform when it vertically displacing in 100 metre swells.
The whole Bespin cloud base thing could be added in the top layers of gas giants - plenty of opportunities for fun in the clouds and again just spacestations in the clouds.
The community goals thing could easily be adapted to provide cargo hauling based opportunities for visible settlement expansion, atmosphere processing (think Aliens), mining and extraction, sending out probes to do prospecting and then help set up mining colonies.
Missions could also be added to rendezvous with agents and "individuals" at remote locations on the surface whilst maintaining stealth (we already have mechanics for that), which gives you smuggling opportunities, or arms deals or other covert nefarious activities.
All this stuff could happen without having to get out of your spaceship or engage in pew pew (not that those opportunities shouldn't exist) on the combat side of things you may have to do some of the following:
- bomb bases
- locate them (imagine having to find smugglers for the authorities camped out on the surface of a remote moon)
- root out a pirate base (or join them)
- fly CAP (Circle And Protect) over a ground based asset, which is being targeted
- escort valuable cargo ships (passengers would be nice)
- rescue a stranded spaceship that's out of fuel or has a broken component you have to send them using a drone
There's a raft of potential survival scenarios as well.
The list goes on and on and these are probably harder to achieve currently than the actual planet surfaces and simulation activities to get down there. In fact the framework items added in 1.1, 1.2 & 1.3 also help set the groundwork for "stuff" to do on planets as well as space and I expect more framework functionality to be added over the next couple of years at least. I don't expect to see planetary landings until Q4 2016 at the earliest though and nor do I expect First Person until at least a year after that, not because the engine mechanics can't support it, but because the asset creation involved in supporting it (apart from maybe basic airless moon base landings) will require a lot of work and time. Specifically I am think of interiors (and the animated stuff like doors, lifts etc) for the space stations outside of what is already visible from your cockpit when docking.