I'm for the buffing / crowd control full caster for combat. Outside of combat it looks like they could use a face, and maybe some roguely bits and knowledge skills.
Sorcerer with twin makes a great buffer, I'll jump on that bandwagon. Start with twin Haste, graduate up to twin Greater Invisibility at 7th. Easy to do Face. Divine Soul (from Xanathar's Guide to Everything) gives you all the fun cleric spells as well - Bless is low level and great for when you want to conserve your highest level slots.
Bards make great crowd control, go with something like College of Glamour (Xanathar's Guide again) for some non-concentration buffing with the amazing Mantle of Inspiration. Rearrange your side on the battlefield, without triggering OAs, and grant temp HPs. Even easier than sorcerer to do Face.
Wizard has all the spells and can swap them out. Plus ritual cast anything in your book even if you don't know it. Load up on knowledge skills. Divination is always fun, or Abjuration if you think they won't protect you well enough. Bladesinger just for the bonus to AC & Concentration might also work.
Don't have a good roguely option for you, but the right background and a decent Dex can fit onto any of these if it's really something you need.