That bike will be good for the kind of riding you describe. The only potential annoyance I see with it is the gearing, which can be changed to some degree.
Before I go further, I should say that I'm a bit of a newb in the MTB area myself, but I do spend an inordinate amount of time comparing bikes and thinking about components, so I think I can offer some useful advice.
The short travel fork is actually probably what you want for beginner trails, and depending on what you mean by intermediate it can probably handle that too.
The main thing you'd get with more expensive derailleurs and shifters is more gears (8 or 9-speed cassette vs. 7-speed freewheel). They shift more crisply too, but if you keep it tuned, that's shouldn't be a huge issue. Just learn to do your own derailleur adjustment (a very handy skill anyway).
The gearing is a little odd on that bike. The 7-speed freewheel, if I'm not mistaken, jumps from a 24-tooth cog to a 34-tooth cog, which is going to feel like the chain fell off. It's a nice bailout option, but it leaves you with the 24T cog as you biggest gear for normal use, which isn't good. Depending on the kinds of hills you see regularly, you might not like that. If it were me, I'd probably want to swap in a 13-28 freewheel. That would give you more range for normal use, but you wouldn't have that super-low gear for getting up really steep climbs.
Otherwise, ride it until something wears out and then upgrade as you like.