DMD uses an auto-combine on small input blocks so it is already out there.
DMD Developer - "... DMD where split stake normal stake or group stake (merge pile together) is automatic adjusted by wallet code and create a zero micromanagement needed POS experience"
While DMD likes to claim their system is different and unique, this feature exists in almost every POS coin. You are still better off managing your coins instead of waiting for the small chunks to combine or you waste too much time.