I've not tried it out yet, I'm still setting it up the way I like it, is there any change at all from FSX's ATC?

No change.

I had Radar Contact working well for FSX but have not yet tried to make it work yet with P3Dv2.  Since there won't be a version 5 of Radar Contact, I may look elsewhere.  The ATC system in FSX was a good start but needs some serious improvements.  I guess that would be a major effort?  Does anyone know if it's even being considered?

I use Radar Contact without problem in P3dv2. I used to use MCE to interact with it in P3dv1.4, but MCE is being updated to work with v2 as at the moment it isn't fully compatible with Radar contact and v2.

I haven't bothered to try the native v2 ATC.

And I'm using VOXATC. A bit fiddly to set up, but works fine.

Just started with V2 yesterday, Apologize in advance if stupid question. Can I set ATC up so it tells me what heading and altitude to fly at when going from point A to point B? 

Radar Contact is working just as well in P3Dv2.2