The Avistar is a good airplane. With the semi-symetrical airfoil and lower dihedral, it is more maneuverable than a basic trainer. I'm sure it could be used for a primary trainer but you might be better off looking at something like the Hobbico SuperStar, Nexstar ARF, Tower Trainer, Sig LT-40, etc.

The engine will work fine also but personally, I'd recommend the OS line. If budget is a concern, go with the .46-LA; it will work fine in trainer airplane. If you don't mind spending a few extra dollars, look at the .46-AX. This engine is one you'll use in all sorts of planes for years to come. The evolution will definitely work though, I just have my own personal preference.

This is an excellent radio. I personally own one. I can see it being a little complicated for a new flyer though. There are all sorts of programming options, binding procedures and stuff that might only serve to further confuse someone brand new to planes. You might want to look at one of the basic 4-channel radios from Futaba or JR. Yes they are 72MHz but they will work just find and operation is very simple plus they don't cost much. You can upgrade to the sophisticated 2.4GHz radio as you advance. The money you save can go into an engine upgrade or field equipment. This is just my opinion of course.

This kit has everything you will need except fuel: http://www3.towerhobbies.com/cgi-bin...?&I=LXL419&P=0

The only other thing I would recommend is a self-powered glow driver. The one in the above kit has a wire and that can be a hazard around the prop. Something like this is great: http://www3.towerhobbies.com/cgi-bin...?&I=LXD697&P=0

Don't forget to buy a few extra glow plugs for your engine too.

Again, this is all just my opinion. The set up you listed will still get the job done.