Picked up and dropped quite a few, but here's my list (or a list that I can remember.)
![Zero Suit Zamus :4zss: :4zss:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Played her a lot when I first got the game back in 2014. I'm talking maybe a solid year. This was when I had no competitive knowledge of the game (which I consider to be better times.)
![Marth :4marth: :4marth:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
My first ever actual main. I played him the most. He was my main for about a year as well (2016) since he was taught to me for fundamentals. I dropped the character multiple times because I couldn't handle the aspect of zoning and the issue of when people got into my space, but I also picked up the character over and over after the drops because I couldn't put him down. I honestly loved the character, and he was the only one that I was able to use well at my current level (beginner.)
![Ryu :4ryu: :4ryu:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Still a goal for me. I bought him because I was always entertained by the idea of having Ryu in Smash Bros. But I can't use him well on 3DS, so I dropped him. Maybe one day once I am able to get a Wii U/Switch, I'll try again (since he is legitimately a goal - for me to main him.)
![Lucina :4lucina: :4lucina:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
I also used Lucina as either a pair with
![Marth :4marth: :4marth:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
or by herself. She fit me better than Marth since I couldn't hit tippers consistently, but I flip-flopped between the two because Marth had a lot more kill options. He still doesn't fit me well, so I just stuck with Lucina for a bit, but dropped her due to my playstyle.
![Captain Falcon :4falcon: :4falcon:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Falcon is a character that fit my playstyle the most (an aggro bait & punish) but since I was too used to having a sword after maining Marcina for so long, I couldn't use this character. So I dropped him as well.
![Pit :4pit: :4pit:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
![Dark Pit :4darkpit: :4darkpit:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
I do remember using the Pits for a bit. I used Dark Pit more since his side B was stronger, but I also used Pit for his arrow control. To this day I have no idea why I dropped them.
![Ike :4myfriends: :4myfriends:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
I did entertain the idea of maining Ike for a bit. I guess I didn't like him very much since he was a lot slower than Marcina, which is something I'm not used to. Like Marth, I played him a lot in Brawl, but I guess since I started my competitive journey, his speed is something that held me back from maining him.
![Falco :4falco: :4falco:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Falco was also an option for me to start my competitive journey with, but Marth was chosen for me instead.
![Fox :4fox: :4fox:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
I did also mess around with Fox, but his speed was just a bit too fast for me. I do like playing faster characters, but Fox was very hard to control, and he was also difficult for me to use.
![Ganondorf :4ganondorf: :4ganondorf:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
I did play Ganon for a short time, but his recovery held me back from choosing him as a main.
![Donkey Kong :4dk: :4dk:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Messed around with him for a bit. I could extended dash dance with him like I could with Marcina, Falcon, etc. but I just couldn't use him correctly.
![Mario :4mario: :4mario:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
I did try to learn Mario, but I found myself not knowing what to do with him (just like Falcon,) so I ended up going for grabs a lot. Dropped him as well.
![Roy :4feroy: :4feroy:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
And now for my current main: Roy. Roy seems to fit my playstyle the best at the moment. It is daunting using a character that has quite a number of bad matchups, and his weaknesses kind of threw me off in the beginning as well, but I really want to work with him to improve. I don't have the biggest competitive dreams - a local scene is as far as I will go. So finding a character that suits me and that I generally have fun with is more of a priority to me than choosing someone who is good.
I may also entertain the idea of going back to
![Ryu :4ryu: :4ryu:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
or
![Zero Suit Zamus :4zss: :4zss:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
down the line, and I may even head back to
![Marth :4marth: :4marth:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
once I am better at the game. I love these characters to death, so the thought of being able to use them when I am adequate enough to do so is super exciting, and it makes me happy.
Well, that's my list. I did go through a **** ton of characters, to be honest. xD