Whats next to increase power?

I’ve reached the following milestones but my squad is merely +20M in power. I see some players with +42M…… - I reached level 30 HQ - I unlocked level 10 troops - I elevated tank center to level 30 - Left side of drone reached level 8

I know I still need to elevate two heroes to 5 stars but still….

Where is the gap to reach those power levels? Its getting frustrating.