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Marowak is already confirmed on my team, and it actually mitigates the lack of fossil Pokemon at least somewhat. Rowlet is my most likely starter choice at the moment. And then we have the sand castle Pokemon, which seems to be really good ingame with its coverage and reliable recovery, and is at least Ground type (close enough to Rock).
And please, don't start on Ultra Beasts. They sum up everything people ever feared about GameFreak taking the wrong routes with new designs: humanoid, robotic, overdesigned, impractical, unnatural, soulless..
I see what you mean about the UBs; They're all a bit... eep. Though I have a feeling they're designs are rather story related (I stumbled upon a huge spoiler the other day).