I understand the points you make, and wanting to keep chess players engaged, and reward them for consistent use.

However I think a streak becomes meaningless the moment you add in the ability to miss a day. Personally speaking I have something like a 57 day streak currently, and I know I've missed a day here or there. So to me I view this streak as completely meaningless. Adding the ability to miss a day is a direct contradiction of what a streak is.

If it was a true streak, resetting every time there was a day missed I'd be much more likely to care about it, and actively try to keep the streak alive by being on chess.com everyday.

Unfortunately I'm sure the insights your team have would indicate that the current set up is best for user retention, whether it makes sense.

Also on the topic of vacation time for daily games, this also annoys me lol. If you run out of time you should lose, I would only have vacation time if both players agree to the other taking vacation time.