I've had my 23' for 25+ years with the old AQAD40(150HP) engine and Duo Prop out drive. I believe my package is just under 1200 pounds and can't imagine going much heaver. I think it would be a bad idea to add more weight to the back end and have the deck drains below the water level.
Width is 7' 2" at the stern.
When considering horse power, you need to ask yourself how fast can I go on an average day and how far am I traveling to get to the grounds. Here in San Diego, we travel 10 to 50 miles offshore at 18-25 knots on an average day. 170 HP in the 23' would be about right for our conditions.
I don't know of any 23' owners that re-powered with a lot of horse power. There are several 26' owners that went up over 250HP and are to scared to use the extra HP they paid for. The hulls were designed to run 15-20 knots and get a little scary over 30.
Mike