Would the saito 150 fs be too much weight for the 90 size seagull yak 54? Bc it calls for a 125 saito but I want unlimited vertical capability

How much more power do you think the 150 has over the 125? Ever give any thought about something like the YS 140 sport or other high performance engines in there line? I see the term unlimited vertical all the time and wonder about it and what people expect out of different engine/plane combos.