I either use vegeta or piccolo.
Vegeta - His base and ssj speed is equal to goku and above several characters, his attacks are harder to use, but are very powerful (BB is a rort it is so evil how fast it charges) and i enjoy a challenge.
Piccolo - MY favourite
SBC charges very quickly. tracer ki blasts are funny, and eyelaser + kiblast 0wns when you melee someone into a building. He transforms quickly in relation to the other characters.
P.S I think buu is kinda crap, sure mouthblast is powerful but costs a lot of ki, is a slow attack even once fired(in comparison to charging other ki attacks), either piccolo or vegeta can fire a SBC or BB at it then teleport up to where you are and just wait for you to finish your beam struggle... muhahaha!
Other characters that i like are freiza (telekenisis is so cool, even though i cant hit anything with it lol), cell (got like every attack, why hasnt anyone mentioned him yet?) and krillin (whoa speedfreak!).
This is kinda a flawed discussion every character is so different, goku buu and trunks are OBVIOUSLY not the 'best' characters, but yes they are very popular.
Got one word for you Cy, DISCS. three characters have them, and none of the characters you picked do. Discs are stupid if you only use them, but can be such awesome ways to buy yourself tie or sacrifice your life dearly.