If the pro is a good teacher and is willing to evaluate your game and strokes and not just fit you into his/her predetermined form, then definitely take some lessons. That outside perspective can really help you along. Taking some video of yourself is also really helpful.
More generally go for it. 46 is not too old to still play at a high level and improve. Like you I took a break after my 20's, but it sounds like you were quite a bit better than me. I didn't play much in my 30's to mid 40's. I stared playing again a few years ago. I'm 50 now and I'm hitting better then I ever have. I took a mini-set off a high school varsity player a couple of weeks ago, and I've taken games off of 18 open and 5.0 players. No way I could have done that with the game I had in my 20s. And I'm still trying to improve.