I don't know if this answers the question, I hope it does, but I don't think of my preferred party in terms of mechanical synergy with my character's class. I honestly think in DnD5e you can mix almost any 4 classes together and have a perfectly functional party that can easily get through the whole game. Worst case scenario is taking more long rests than usual.
Sadly I can't say I really 'like' any of the current companions. This hasn't ever happened to me outside Larian games. So instead I intend to pick those whose stories intrigue me or I think they fit the campaign and will have interesting content. As of now I'm thinking:
- Shadowheart. In Sven's own words, her artefact is something they really want us to experience. Also she has enough Morrigan vibes to give me proper Dragon Age nostalgia.
- Lae'zel. Missing out on the githyanki companion in a campaign where mind flayers play a major role would be a sin. I only hope she becomes less abrasive over time.
- Wyll. This would be the first crpg where I'd see a proper warlock story that actively involves the patron. This is my 'flexible slot' and I'm ready to swap him out for Karlach or the unrevealed companion if they prove more interesting or likeable.
