MP drain, what are you talking about?
When we're not talking about call-in meta, Ost pays the most in terms of MP for its tech.
Ostheer: 200(BP1) + 120 (T2) + 200 (BP 2) + 160 (T3) + 200 (BP 3) + 160 (T4) = 1040 MP, not including the bunker or the initial T1 cost.
Soviets: 120 (t1) + 160 (T2) + 240 (T3) + 240 (T4) = 860 MP, not including the grenades of medical upgrade.
USF: 200 (LT) + 200 (Cap) + 240 (Major) = 640, not including any upgrades or ambulance.
OKW: 200 (Flak) + 200 (BHQ) + 200 (Mech) = 600, may be a little off.
Of course Ostheer has no upgrades as they are included in the BP upgrades, but those teching costs in terms of MP compared to the other factions.
Infantry-wise we're no more expensive than our Soviet counterparts, but we can bleed more if we lose too many early engagements as grens are 30 per member and even pioneers come in at whopping 25. Of course, we can cause the enemy to bleed, so it depends on the engagements.