You need to better balance between offensive and defensive part of the game. Right now the offensive part of the game is way too strong. A few upgraded panzerwerfer in rage mode can roll over just about any base in this game no matter how strong the base is. You need to increase the range and fire power of all defensive towers. You should also increase the strength of all wall barriers as much as 20 times what they are now. If you allow the bases to being able to defend itself, you will have more members working on improving their base. Currently there is no skill in attacking a base. It was a good start with the new heavy tank mine, but you need to go higher than just 5 lvls. Damage should be at least 3 or 4 times what they are doing right now.