Major Tip:

When going for the biker boy trophy if u get lower than 75% just restart at last battle and it will put right at the beginning of with a cool new character. Just keep trying to you get it!.

Chapter 4 is the biggest detour so far in a very pleasant way. Jessie reeeaaallllyyyy want the D so bad.

Is it better to play the game on easy, as i am hearing bosses or enemies are like bullet sponges. Also is it worth doing the side quests as i hear they aren't good. 

No and yes. 

The battle system is heavily centered around Staggering the enemy  (not the degree of FF13 though); once staggered maximum damage is done a health falls fast. Side quest are par with FFXV, not terribly excting but terribly terrible either. Some weapons/armor/Materia/ and reputation are gained through sidequest. Dont skip them. 

Currently on Chapter on 6 I think? Just got moogle summon. I am really enjoying the extended trip to Reactor 5. boss fights are overly chaotic in sometimes a not good way.

Boss fight sometimes overstay their welcome for sure. Especially when they render two of characters useless for a while because they decide to go out of melee range.

Does she really say it?

She might as well. That goes double for Jessie. 

Ice Magic sucks. The damage only occurs during the shatter part of the animation so If you manage not to trap the enemy in the initial animation they can just waltz outta there. Makes dealing with seahorse enemies a pain, but on the flip side elemental lighting on Barret is a wash. 

You can link the ice magic to your weapon to deal with those seahorses.

Yea I know. I gave Elemental to Barret because I find dealing with machines to be annoying because their Stagger gauge for the most part only increasing with Thunder magic to be the greater of annoyances.