I like the idea of a spec class, But I think the T-Spec is a bad deal for the simple reason being a 4 wheel drive too many moving parts, too complicated. I think the quality of the vehicle suffers. I think a spec car should be 3 things. Simple, durable and inexpensive.
Simple so newbies can learn about RC cars and simple is also less expensive. Durable because newbies will tear up some cars while learning to drive. Also its no fun bring at the races when your car is broke and hard to fix with many parts to take on and off. Inexpensive so people who would like to race could afford it.
I think the Legends cars were on the right track but the suffered from limited adjustability. I think the old spec pan cars were the closest thing to a good spec car.
My idea for a good spec car would be a 1/12 scale pan style car. The motor would be the current 21 turn spec motor. Batteries would be 4 cell with perhaps 2400mah unmatched stick packs. The 2400mah cells are reasonable priced these days. 1/12 scale bodies less plastic, less cost.
Tires would be rubber similar to the ones used on the touring cars with a limited number of compounds. The rubber tires last longer than the sponge ones. The chassis would be either a composite plastic or a G10 fiberglass to keep cost down. I could realistically see the manufacturers offering such a car for no more than $125 MSRP for the roller with no electronics. Street price less than $100. Also bearings would be included in the kit. Bushings are a high service item
The electronics could be limited by the rules also. The batteries would have high quality connectors, not the cheapo Tamiya ones.