Hard Shifting and Squeal

On October 10, 2015, I purchased a 2011 Outlander 800r Max XT-P with 7500 kilometers. I drove it home, following my brother-in-law who also purchased an atv that day (2015 1000 Max Ltd). The drive took 1.5 Hrs. Items which I questioned:
1. I noticed mine was hard to put into gear unless I "humped it" (phrase picked up from reading some online posts).
2. I did not use it the following day but the very next day, I started it up and immediately it squealed at low RPM. That lasted for several minutes, then it would only squeal when I blipped the throttle (revved the engine). After a short drive it was back to it’s norm again. After reading several posts, I have ordered two new fully sealed oneway bearings along with the Isoflex NBU 15 grease.
3. I also popped the clutch cover and found that the belt constantly spins at idle. I am receptive to economical mods at the time I replace the bearings,, but I do not want to spend too much at this point until I’ve ridden it longer. It has standard sized tires Maxxis Mud 25 x 10 x 12 rear and 25 x 8 x 12 front.
4. Also, ck’g the air filter, it seems heavy, so I’m not sure how much it should weigh when new. If anyone has an idea pls let me know. Also, should I change it out,, I would like ideas on a dual filtration system.