No problem, actually.
Nevertheless, I added 100-150% to all missions, except base defense, base assault, interceptors, gov ship and ES missions, and any ninja (bc fuck ninjas)
If someone want - here is file (don't forget make a reserve copy). Additional meat to EVERY difficulty, not only hardest.
For example, humanist mansion: now there is 2-6 mobiles and about 80 soldiers.
The main problem: I do not know, how many spawn point exist on maps. When I added 90 soldiers to Bandit town, game crashed.