I'm playing with 5e rules so with all do respect, 2e doesn't tell me anything about the game since I haven't played it.
Not unless they're interested in assisting them in their success. The game is collaborative and everyone at the table should be trying to help each other succeed. If not, seriously why aren't they playing video games instead?
If I didn't answer your question, feel free to follow up and try to elaborate a bit more?
This would be remain in game but yes, one after another or maybe 2 at a time if the PC's goals are similar and can be handled consecutively. However I would imagine there being a personal investment from other players to see them succeed.
Think about it in this context? Sports movie training montages, anime level boosts in power, outsmarting your opponents and or enemies. Things like this just seem like they'd put fun into leveling up.
Personally, I find leveling up in DND 5e to be pretty monotonous. So after hearing about this on tiktok, I've elected to start using this Homebrew rule: Individual Quest line Leveling. Your character has to go on their own individual quest and accomplish something in order to gain levels.
Is it weird that I wanna play a blood hunter just so I can do the Sasuke chidori slap?
Glad I was able to help you out a little bit.🥰
Just a suggestion but perhaps you should tag your furaffinity account?