I also haven't played in a very long time, but I had 600 hours in the game, so I feel qualified to respond. I used to almost exclusively play control point maps btw, and I was the type of person who played the objective super hard.
My class with the most hours was soldier, and it was the most by a long shot. The next highest class was like 50% of the hours I put into soldier. I liked soldier in general because of the rocket jump mobility and the firepower you got from the rockets. My favorite loadout was the original for primary weapon, because I liked how it shot from the center of your screen, the default shotgun, and the rail spike melee weapon for the bonus to control point capture.
My class with the least hours was spy. I just didn't really like slinking around to try to take people out from behind when I could just blast them in the front with a ton of rockets instead. The only time I'd really use spy is when my team got down to the last control point, and the other team was entrenched really well in their base. Then I'd switch over to spy and do kamikaze runs of disabling their sentries.
That's the life, right there