Oh I meant painting the bases ha ha. As everything in the pic looks very unified!
My bad.
The five members all have different basing techniques. One prefers a Gilder style with brown and green gravel and sand mixes, one uses sand and static grass, one use brown and green bastex, one used gravel with static grass and silfor tufts.
I use polyfilla with sand and seven different grass and flower tufts.
As long as the individual collections are all of the same style it seems to work well on the table.