Agree with all the posts.
Interesting i think it is more to do with technique and basic strength than power at basic level although clearly power helps for more advanced tricks.
My son could flick his mountain bike about for many years at will, but could not flick his Beta 80 or Gas Gas 125 or my Sherco 250 as he lacked strength.
After not practising trials for about 18 months, he could on trying a 4RT a few weeks ago, flick it about surprisingly easy as he is stronger.
A modern 250 may suit you better. Take your pick Beta, Gas Gas, Sherco, Vertigo etc they are all good and light, nothing wrong with the bike you have albeit a bit heavier and harder.