Tree groups need to be visible on the reclaim overlay since they are important to reclaim on many maps. A more generalized solution that shows energy contents on the reclaim overlay instead of just mass would be preferable to showing some arbitrary dots. Though currently tree's are pretty much the only prop containing energy.
You can already determine the trajectory of units by noticing the trees falling over, or if the tree groups have enough mass they appear/disappear on the overlay already. You also already get free intel by seeing what bits of mass your opponent has reclaimed. 99.9% of people probably don't utilize this information, but weirdos like me and ZLO sometimes look at the falling trees to know there are labs coming, or to know precisely where to raid engineers that are reclaiming.
Having labs not break tree groups makes sense to me since they are tiny units and I don't think the deliberate breaking of tree groups is an important game mechanic anyway.