Personally I wouldn't cut the base, I think it would become to weak.
You could make a shorter base, either out of wood or just cinder blocks with a plywood sheet (can cover with a black sheet or something) or a short coffee table, plus then you get storage under the tanks. (I've done both of those before)
Or - what I do, is use the base and get a step stool for ease of cleaning/access to the topmost cage.![]()