If you had a partly stuck ring or two and all you see is streaks at the ring gaps, that's not bad. i can't see the connection between compression and the high rpm stutters. anyway, 120 sounds fine.
as an experiment, try increasing plug gap to about 0.040 or 0.050 or more.. i'm thinking if things get better it could confirm the plug is wet-fouling at high rpm. If things get worse ignition might be weak. Either way it's a clue that can be added to the practically empty box of clues.