My rule of thumb:
1 day is enough to do only the attractions that are unique or different enough. Especially if you're willing to buy a couple of individual Premier Passes (Crush and BTM)
2 days are enough to do everything.
3 days to smell the roses.
With 4 days, only the most hardcore fans won't get bored.
But it depends on your touring style (are you a rope drop to close commando style visitor?). Do you like shows? Are characters a must do?
If you don't mind the hotel transfer, the onsite hotels are nicely themed also at the value level, otherwise the commute from central Paris is not too bad, 45 minutes by train and the station is right in front of the security checks (literally, 1 minute walk). I would not the recommend the opposite, using a DLP as a base to visit Paris (unless the focus is DLP and you want to visit Paris only for a day).
This thread has a lot of useful tips:
https://www.disboards.com/threads/karin’s-disneyland-paris-first-timer-tips-2024.3950886/