Just using the numbers you started with. I am running a stock tranny with my stock radiator right now and have no problems other than launching. Yes, you should upgrade most anything under the hood if your going to be building the car. But most people don't have 10 grand to drop into thier car at once. (at least I don't) So you build it piece by piece. Saving up for big upgrades like a head swap or a turbo kit. There are alot of you should's that go along with building a vehicle. But in alot of cases you can make do with what is already there. Just respect the parts that your straining and they will live longer or at least until you can afford to replace them. You can shatter stock differentials with a stock engine if you beat on it.
The focussport head is $1500 with valvetrain in it. If you spend an additional $500 ($150 for the cam gears and $350 for the cams just like in my breakdown) your at $2000 for the head your talking about. I listed everything there, just took the parts off of your list not absolutely required to make 200hp live under the hood.

95 Contour, Custom EVO bodykit, 2.0l, PNP Focus head, Stage 2 cams, Je pistons, Eagle rods, 4in1header, 2.5" header back exhaust(complete stainless), D P nitrous, ram air intake, 10mm wires, flamethrower.