You might want to use Roselia, since it can handle Quagsire easily. You might not want Quagsire to use Mud Sport, since it makes Luxio hit Floatzel a little less hard, and it may result to a bad match up. Roselia can OHKO Quag pog, so there shouldn't be any problem ready for you.
Also, Roserade (though gives burden to the team members till it evolves) reduces burden of Floatzel by single handedly taking on Bertha (Floatzel can sweep most of Flint's team and Lucian's team). It also helps in defeating Gastrodon, which walls everyone in your team.
So I would recommend you to add Roserade to your team. A simple move of Grass Knot and Petal dance could help your team greatly.
Hope this helps :)