What tiers do you enjoy playing in?
Mainly DP Tiers, especially the lower ones. DP LC is totally my favourite, but OU is ok as well.
I don't really enjoy BW OU because everything is overpowered or overbulked, you have a hard time if you don't use the same shit over and over, it simply does not depend on prediciton and planning if you win but on the match up and how good he is at clicking at volt switch and u turn! BW Lower Tiers like NU, RU and LC are ok for me I kinda can enjoy them, but BW as a whole isn't as good as ADV and DP were.
Why do you enjoy those tiers?
I love playing DP because for me it is the most balanced and rich in variety, you can be succesfull with any playstyle. The only thing I dislike about DP OU is the overuse of Heatran but that's fine I guess. I'm generally a huge LC fan because it is a fast metagame where prediction can win you the most difficult match ups. Eviolite kinda destroyed that but DP LC and ADV LC were simply genius metagames.
What tiers do you want to learn, if any?
I'd like to get into Triples and VGC, used to love DP OU Doubles but nobody plays that anymore lol.
What advice do you have for someone starting to play in one of the tiers you play in?
Think when you are making the teams, simply try to cover every type of a Pokemon and if you are not stall be sure to have a lot of speed and priority in your team. Hazards are helpfull too. If your team is slow then have something to spread para. Going first is important because it helps against hax!