I would second the nappy lady questionnaire..
And also second the miosolos aren't designed for night times due to having a microfiber core - we used them in the day between 5-12months ish and needed to add one or two little lamb double bamboo boosters to get a few hours out of them.
I've seen hemp boosters recommended a lot if you wanted to try boosters to go in what you've already got - I haven't tried hemp myself yet though.
I did a similar thing and started trying to use cloth nappies on my nearly 3yr old just after he potty trained, so for naps only in the intention to also use at night - but didn't have much luck - I used little lamb pocket nappies with bamboo boosters at the time.
I did buy them knowing we were trying for another baby though and that we'd hopefully use them on the second child which we did and are..
We don't use cloth at night but have occasionally tried it out and tend to go for a two parter like a little lamb bamboo sized nappy (bamboozles seem popular too) - I got my little lamb bamboo nappies cheap second hand along with some motherease airflow wraps.
We've also had luck with motherease wizard unos/duos at night in the past but these are like gold dust to get hold of at the moment and not cheap! 🙈
There are some fab Facebook groups for cloth nappy help and also try Facebook for preloved nappies - I've barely bought any new.. Your miosolos should also sell well if you decide to try something else..
Sorry I can't be more help but I wouldn't know what fits well on an older child (my youngest is now 2yrs 3months in cloth daytime) - it's been a lot of trial and error though.
Do you have a nappy library near by that you can hire different nappies to try?