These are the characters I use the most, and I think I'm pretty good with. The characters I'm the best with and enjoy the most are on the top. Also the costume I like to use.
>Wii Fit Trainer (Yellow/Male)
>Ness (Yellow)
>Mii Gunner
>Jigglypuff (White FR/LG Hat on Wii U/Red Rose on 3DS)
>Dr. Mario (Blue)
>Mii Swordfighter
>Villager (Purple and Yellow)
>Kirby (Yellow)
>Samus (Pink)
>Toon Link (Purple)
>R.O.B. (Pink and Yellow)
King Dedede is my absolute main to play in Smash 4. I never cared about him back in Brawl but here I really love him now. He's got almost the similar nimble & power as Bowser, but he's quite more ranged with his hammer & could have some combo potential. He's my favourite character to play as in Smash 4.
Never played the original Smash or Project M, the very few times I played Melee I used Kirby, Ness, or the Ice Climbers, Brawl it was Olimar, Lucas, and Ice Climbers, and in Sm4sh I use Olimar, Peach, Robin, and Mii Brawler.
SSBB: Mario, Luigi, Kirby, and Toon Link, mostly.
SSB4: Mii Fighter and Diddy Kong. When I played Smash 3DS as Diddy Kong, I became much better at using him.