I started an injury count this season, im at 10 currently. No powertrain, rare normal training, 2 matches per day...

systematic approach: Heal only the important guys up (4 stars in your case), wait out the short injuries (2-3 days) and replace the mediocre players (3 stars or less) with long-term injuries. Still, buying new players costs tokens, too.

use vids only for red packs, do friendlies against a 2nd account with low tackling (hard to do friendlies when half the squad is injured, but start doing so to stack reds when youre ok again).