I can only speak for my 26X, but the PO did me a lot of favors by putting the two batteries and the two 9 gallon fresh water tanks under the forward V berth. My 13 gallon head holding tank is located under the aft dinette seat, but is rarely that full.
My two 9 gallon gas tanks are under the cockpit seats in the spaces designed for them. I have not measured my boat trim, but I routinely empty my ballast tank underway. With just one or two adults in the cockpit, the boat starts out with a higher trim angle but quickly, when it gets on plane, levels out nicely. With 5-6 adults aboard, I ask one to move forward to the forward hatch to help balance out the boat when starting to empty the ballast tank. That one person forward is sufficient to bring the trim back to close to level after the initial higher angle just starting out. So, I suggest moving as much equipment and gear forward to accomplish a better trim. OBTW, never owned a Volvo, but I sure enjoy my Gevalia coffee! Cheers!