Muticlassing without paladin is a steak without salt :P
Hmm I would set some limited expectations. My strong guess is that Hexadin of Warlock will not be released in BG full release which makes Warlock/Paladin build is much less popular. There are of course other multiclass possibilites.
I don't expect -at this point- to see Hexblade warlock in the official release of the game, at least at start. Maybe however, we will see it, either because of story reasons, or because it would fix the problem of melee warlocks not working in the base PHB conveniently.
Another way would be to buff pact of the blade, but you also need eldritch smite ability, without it, there-is-not a melee warlock. It would be much faster and easier to just put hexblade in and be done with it, than trying to rebalance pact of the blade, along with any imbalances that arise because you changed an already established and -somewhat- balanced system.
Mizora is obviously not the raven queen or a sentient weapon, so Wyll can not really be a hexblade. Some more XGtE invocations (like Eldritch Smite) would be cool, but I would not expect them at this point.
Imo, the easiest way to make meelee warlocks work is just add hex warrior to pact of the blade. That is the main reason why only hexblades work as meelee warlocks atm.
