It's truly up to you so there are no wrong answers, except for maybe reducing the default tip that is charged to your account. I'd say that's a wrong answer.
As an anecdote, on our last cruise, we nearly doubled the default tip for the room attendant, server, and assistant server. We have a messy toddler and all 3 of them were super accommodating and not annoyed. We only saw our head server once so I think I added maybe 5 bucks and called it a day for him.
On our next cruise at end Nov beg Dec, I have budgeted doubling the tips for everyone (attendant, asst server, server, head server), assuming we get the same level of outstanding service as we did before. If the service stinks I'll just leave the default tip and call it a day.