Ok that's good man, although a little broader than I was talking. Here, take a look at mine.
*Notice how I removed anything that I don't want to play, this really helps you focus on just the stuff you enjoy playing rather than everything.
Now the naming is a little weird since I only actually main Sheik and Secondary Lucina. But for sake of example this is what it should look like. Every character that I have played and have some knowledge about in in the tier list and I picked out my favourite characters. Which are the top two rows, I then listed the rest of the characters I play for fun or have some knowledge about.
What I got from doing this was a list of characters that I would definitely play, basically anything in the top two rows was a contender. I then ordered from best to worse at my current skill level. I then looked at who I enjoy putting my time into which left me with Sheik who I play almost exclusively in tournaments and for actually practice etc as I found her fun and the most rewarding to learn, and then Lucina who I really love playing and love as a character who helps me practice my fundamentals etc.
Since I actually did this I updated this and almost exclusively play the characters in the top row unless I am really feeling mad adventurous. Which is fine, but you do want to limit down to a few characters, or at least a few characters that play similar (ie Marth is quite high for me but mostly due to being almost the same as Lucina). Of course this really only applies if your really looking to push yourself and attend tournaments.
The main thing you have to remember when picking a main its all about who you play when you need to be your best, don't worry if you have a bunch of different characters you like playing when messing around in friendlies but you have to be sure that you put the time into your main the most and don't switch off your main in tournament unnecessarily.
Also added note, some characters have weaknesses and strengths. It is hard but try not to look into covering your characters issues until you are fluent with your main. It tends to make people flick between characters because they get extremely caught up in the counter picking. Practice makes perfect and most characters can still put up a hell of a fight even in disadvantages situations because remember your fighting another player not there character.
Your on the right lines though, I'd recommend Ike since he has strong fundamentals and is a fairly strong pick anyway