Druid seems pretty cool. Summoning focused, a bti worrysome if they lose control of the summons, but otherwise pretty neat. I do like it overall. Maybe a bit stronger than Land, but definite props overall.
Cavalier is... meh. The extra proficencies are lame. If you take something other than Handle Animal, it better be because you already know it. The expertise tricks are... iffy. So much of the mechanics are built around a mounted charge, it feels like a one trick pony pretending to have more tricks. Relentless is especially strange. One dice when you need two for the charging.
I actually like the new paladin. Its a bit odd about the psychic damage, but the whole "being awesome at fear" trick is pretty cool. I like it a lot, and could see myself playing it.
Celestial Warlock, on its own? Crap in a crap basket. I don't care that its a goodly patron, I care that its pretty much terrible for a Blade or Chain pact. You want a celestial pact, make a celestial familiar. Make some mechanics that let the blade work with it, and not focused entirely on spell casting. Make the cantrips competative with Eldritch Blast+Hex if you want us to use Sacred Light instead of EB. The healing is nice, but we're going back to long rest instead of being short rest focused. Warlocks should thrive on short rest abilties. I do like Celestial Radience, but Searing Vengence is... iffy. I don't like that kind of "risk your life" mechanic, because it encourages stupid actions like running into the middle of a fight to get knocked around and nearly dying like a masochist.
So, final thoughts.
I like the new druid and paladin options. Pretty cool and thematic.
New Fighter is iffy and still is still crap at anything outside combat.
Celestial Warlock is going to default to Eldritch Blast + Hex again because its so awesome, and needs support for Chain or Blade if those are going to happen. At least an archon or some other baby angel type for a familiar.
Warlock invoactions are fun, and there's meaningful choices to be had here. I do miss Glyssa based stuff, however.