It kind of depends on how you're using BLM's mobility tools...

If it's to use them reactively to prevent dropping AF, then yeah, it's quite limited because you have only 2 triple and one swift (and maybe a F3 if you're lucky).

If it's to use them pre-emptively to create a map with the moments you need to use them, then BLM is incredibly mobile considering the mechanics.

Leylines is a different story, you need to know the fight to use it well, but that comes alongside mechanic solving naturally, I feel it's part of the fun learning the spots where you should place them every 2minutes.