I think atlas marshal bases need to be changed, at the moment t4s and t5s are dominately owned by one mega alliance, and there is no quick way to actually conquer a t4.
Small ranked teams have normally a select few members that are level 580 plus and they just put them in marshal, therefore making the castle unconquerable for a lot of the atlas teams. For example a ranked 200 team holding a t4 or even a t5 should be hittable and conquerable by another ranked 200 team, but arguably that team just puts a 600 level base on marshal and the other team has no chance to conquer it.
The way the marshal is designed I believe is outdated and needs to be changed either to have no marshal base on t4s or t5s same as t2s and t3s, or another way would be you have to put your lowest dp base or level base on as marshal. Then that would mean that a lot more teams can actually conquer t4s and trying to break into a t4 area and take more castles would be easier, where things stand atm a lot of teams hide behind thier high level player marshal and taunters and can hold several t4s because they need to be warred to take and basically abandoned.
Especially with the new glory scaling, where it makes a lot of teams get no glory out of t2s or t3s, therefore t4s should be more violatile and easier to conquer and take, which IMO changing the marshal would be a good start