Gulfstream

I have the Gulfstream 232 2017 with a 300HP Yamaha. I would not put anything smaller on it. The 300 HP will be enough power to get you on plane quickly and move the boat well. The boat would be best with twins 150s or 200s but it will cost more for maintenance. Twins are easier for docking but the 300 HP is a great option. Good Luck.
What prop do you have on that 300?
 
I had a an 05 Gufstream and it was powered with F225. There was never really an underpower issue. If the budget allows, it a little more speed and power is always nice. Twin 150's would be great . 300 certainly a big upgrade over 225. Good luck i- 23 is a great boat for it's size.