I think the current wreck value and health numbers are imbalanced. In vanilla FA, wrecks were worth 81 percent of the original unit mass value. It was many years ago that naval wrecks were reduced to about half this because naval wrecks were OP. The main reason naval wrecks were OP but land wrecks weren't was because land wrecks are subject to damage from land battles. Primarily, it is T1 mobile artilley that damages wrecks, but any weapon can if it hits them. Navsl wrecks, however, are safe from damage due to hiding under water away from stray shells.
As a result, land wrecks are significantly vulnerable to artrition by random misses from tanks, artillery, and bombers.
My proposal is to reduce all land and structure wreckage value by half (to about 40 percent) and to increase wreck health by 400 percent.
Generally, wrecks have about the same health as their original units. A striker wreck - assuming no overkill - has about 300 health. Increasing this to 1500 would make striker wrecks greatly more resistant to damage from stray shells and would reduce the randomness in how wreck fields are created.
Also, with 81 percent reclaim on structures, it makes more sense (based on mass) to always reclaim and rebuild from scratch instead of rebuilding from a wreck.