Okay, so here's the thing: when it comes to car setup, road-racing & auto-x require different things than drag racing. Typically, something you would setup for the auto-x will end up hurting you for drag racing, and vice versa. I'm being somewhat general here, but it's a good rule of thumb. Since we are talking about tires and wheels here, that's what I'll focus on as my for-example. So. For example, if you want to road-race/auto-x, typically you get the widest wheels that will fit. You then put the widest tire on the wheel that you can *while still maintaining sidewall rigidity.* That last bit is the important part. Don't go throwing 275 tires on a 8" rim. Even if the tire "fits", you will have too much squish on the sidewall because the tire is just too wide for the wheel. When you try to take a corner at speed with a squishy sidewall, your car will squirm a bit, as there is too much give. This squirming can lead to unbalancing the car, and just an over all crappy feeling when driving. It hurts confidence in the car as well.
The corollary to this is if you are drag racing, then a squishy tire is what you want. It will hook better on a straight line launch. And since there are no corners in drag racing, it doesn't matter if it feels squishy during cornering.
So there's the dilemma. My suggestion is to decide which you are more likely to do, and focus the tires on that. If you are really 50/50 on the auto-x and drag racing, then I suggest you focus completely on auto-x and get tires for that. You will still hook decently at the drag strip. If you have the budget (which it looks like you do) then buy two extra wheels for the rear, and mount up a tire with a squishy sidewall. But honestly, unless you plan on dragging quite often, this is a bit of overkill. If you don't drag that often, the tires will just sit and dry rot. So your call. If it were me, I would buy 4 wheels, mount up some good street/road race tires (DOT legal but in the 100 - 250 treadwear range), and use the extra money saved to buy more tires when these wear out.