it tends to flip the plane nose-over-tail if you have it controlling the ascent too - all of a sudden
A bit like real life there, then

If you want to end flightplans at locations other than airports, create and enter your own virtual waypoints and stuff like that, why don't you look at ACS-GPS?
Alain Capt first did it for FS98 and I know it works well in FS2002 because I flew with a panel with it in (replacing the default GPS) only a few days ago.
It's very much like real life - but it's more work (just like real life) and ideally you need charts of the area you're flying in (just like real life) or navaid/route planning details.
So it'll really only appeal to serious IFR simmers - which is why you hear so little about it I guess.
Roger