Captain Falcon, Mario/ Dr Mario, and maybe Shulk or Jigglypuff.
If you want a fighter who constantly attacks it would most likely be Captain Falcon, since his specials easily covers most of the stage. He's the best one for chasing after opponents, and can't be approached easily.
If you want to be combo heavy you'll want Mario, since his moves are quicker with less knockback.
Shulk is really good if you use the monodo speed to quickly attack. Plus his attacks are disjointed and have long range.
Jigglypuff has an easy time approaching in the air and getting close, mostly consisting of aerial follow ups.
You should have a character that can get around easily, not like in dash speed but all around, on land, air, and offstage.
