Well to be honest both game types are pretty good but they both have their perks. Kill Confirmed is easier to play and if you stick strictly to getting all of the tags you should be earning 3000-4000 exp each game. But in Hardpoint you do get more kills and if you're focused on ranking up your gun you can rank it up pretty fast. You do get a little more exp in Hardpoint for every kill you get inside the marked zone. Also in Hardpoint, if you stick to getting the Hardpoint and killing everyone off of it, your kills should range around 40-60. But you should only be earning 2500-3500 exp.

Hope this helped.