These are currently quite useful in the 1-20 game... As they should be since they cost 3 feats (4 if you want to/can get Empower Healing or Maximize) plus 6-10 Action Points.
They are not very useful in epics. Plus there are multiple EDs abilities that are better than the halfling dragonmarks.
With the new pass, could you please take a look at halfling dragonmarks again? If nothing else, I would suggest you make them regen slowly (like Lay-on-Hands).
Lowering the feat requirement to 1 would make them useful to builds other than fighters.
Halflings could use a little love...