I always tried to avoid CCGs because of the business model (and trying to keep my gaming budget within some reasonable limits). I can't really answer most questions here since I never played Magic (I do own a few thousand Magic cards though, because together with sleeves they are perfect backing when constructing print'n'play games and for my own game prototypes, and Common MTG cards are very cheap/free).
I collected some
Pirates of The Spanish Main because of the cute little plastic ships you got (some of the cards were thick plastic like credit cards with ship-parts die cut that you pushed out and made little ship models). Irresistible.
Got into Star Wars Miniatures 5 years after it went out of print. That was a good thing because I have made up a nice collection pretty cheap buying old minis/cards without having to be tempted by boosters. Very good game and you get quite nice pre-painted miniatures to go with each card.
Collected a bit of Dice Masters because the superhero theme in the Marvel/DC decks work for my kids, and I collected some of the D&D cards. It is a good game, but I am only interested in it as a casual game. Unfortunately the theme and rules are better than the non-collectible related game Quarriors, or I would just get a few boxes of Quarriors instead and be happy with that.
Bought some Pokemon cards because my kids of course started collecting, and I wanted to play with them, not just see them collect lots of cards without using them for anything. So I bought some cheap singles just making up a small deck so I can casually play with my kids, and we have played a few times, but not as much as I hoped to. It is somewhat entertaining as a game at least (much more interesting than the combat systems in any of the digital Pokemon games I have seen).
Recently bought some Star Wars: Destiny because I tried the game and it is an excellent game. Very good design and bonus points for theme. I hate that it is collectible and have tried to get a reasonable casual collection to play with, but they did a really good job I think at making the game frustrating to play casual unfortunately.
OK, I guess every collectible game I got into had something more than the cards, like miniatures or dice, not only dice, except for Pokemon. Also never thought of playing competitively, just trying to get small decks for casual play.