From what I understand, a balanced D&D party needs for archtypes: A melee fighter for dealing with other melee fighters, a rogue for detecting and removing traps and locks, a caster for dealing with enemy casters, and a healer to keep everyone standing.
A party limit of four really completely kills gameplay diversity in my mind. Are there any good multiclasses you can do with a level limit of 10 that can let a character handle two of those roles without crippling themselves at one of them?
Assassin/Battlemaster can find traps and other rogue stuff and deal very high damage
Bard can be both caster and healer, and also fight melee and range (in fact is probably the best mage class in the game)
Vengeance Paladin/Warlock can tank, deal damage, heal and attack from range using eldritch blast
Druid/Barbarian can tank and heal
