I am in the business and have done high-end corporate parties, and I felt the same way when I planned my parents 50th anniversary.
I relied on an upscale invites amazing venue, top -notch food amazing flowers and lighting and great linens and table settings. No theme. I think it helps to have more than one music option (our venue was large so we could have more than one band). I basically used all my favorite vendors.
You might want to set up a great photo op area, where you could get creative with the backdrop and guests could pose for pictures. Or if you do not like the furniture in the restaurant, bring in furniture with more character.
I also commissioned an artist to paint the event(the 50th) as it happened. What I really wanted was a participatory painting where all the guests were invited by an attending artist to paint on a canvas, the artist later unifies all the strokes made by guests to make a cohesive painting, but I could not find that artist. I also wanted to do fireworks, but didn't. In the end, I was happy with what we did, but I guess I just wanted to go "old school" since, as you surely know, everything has been done already!
I don't think adult parties need a theme, but maybe because I am jaded after decades in the event industry. Do what you love, it's for your birthday. I think everyone below had good ideas. You could do a Cotton Club theme Hope it is not too stressful!!!