Let’s assume your arrow length is around 28″.
I’d be looking at 145-165g in front of a 100g brass or steel insert,just to get your spine in the ball park.
I’m pretty conservative about these things so on second thoughts I think you could probably go up to 200g.
I shoot GT 3555’s cut to 28″ from my 45lb longbow with a total of 225g up front an get great arrow flight.
That’s a 100g brass insert and a 125g broadhead,,,with no hesitation in going to a 145g head.
You can buy test field point kits from 3Rivers that I’ve found to be good for playing with different point wheights.
The set I have ranges from 100g too 220g,,,two of each size.
All the best,