as of my idea :
I think bases on Map should have an "Add-on" upgrade which costs Energy. Any base can be upgraded with the "Add-on"
If a level 20 bases is upgraded with an add-on, it becomes LV20+Add-on , if its Lv25 then Lv25+Add-on and so on. The bases can still be upgraded once it has the "Add-on"
What this does is that it allows bases to be captured up to a range of 5-10 adjacent bases from that "Add-on" base.
MY SECOND IDEA :
Transform the map by doing all of the following :
-Change the map into and OCTAGONal shape, increase the total bases to 1 000 000. [ each base is adjacent to 8 more bases ]
*Chaining can still be done with this, its just that there are 8 directions to hit and there are total of more than 10x bases.
-Reduce maximum bases to 20 , 000 & reduce the daily prize points scale, 1 - 50 - 100 - 5000 - 100 000 - 500 000 - 10 000 000
-Increase ALLIANCE MAX CAP TO 200
What this does :
*with 10x the amount of maximum bases, you can fit in FOURTY (50) ALLIANCES ON THE MAP! You make every sector very active !
*with reduced maximum bases, the map becomes more compact with more alliance.
*Improveing the alliance cap to 200, doubles your total players.
Without this :
*Map is only dominated by 3-5 alliances. If you had a big space, these alliance cant even reach out everywhere, allowing a fair ground for 45 more alliances