A few proposals.

GENERAL:

1. Have a system where you can "lock" equipment for 1 noble coin, this will make it so you cannot sell it to shops.
Currently having multiple sets of equipment is an annoyance when selling.

2. Change the current challenge point system, currently doing tasks is only worth for the grand tasker achievement and for the 4k point weapon.
Make it so you can open one of the 4k point items once you hit overall milestones of 4000 points, eg once you've accumulated 4000 points (even if the points have been used) you can open the chest, then at 8000 point etc.
You could then add a training weapon for challenge points which will give you 100% training over 3h if using a normal training doll or 2h if using a house training doll, this way warriors and rangers can "focus" training instead of exp.

3. Add so you can "lock" a stat on a piece of equipment when rolling on legendary pieces.
For example you have a noble legs with 4% MR, 4% PHY, 3% EXP and 3% Gold, you would be able to pay 25 nobles coin per slot locked with a maximum of 2(or 1) slots being able to be lock, so I would lock EXP and MR it would roll all slots but the locked slots would only roll their locked stat (so it would roll MR again, so it could be 4%,5% or 6% etc)

CLASSES:

Ranger:

Currently the problem with ranger is the huge reliance on skills and their talents, a few proposals which would help with that but not increase their output by much.

1. Increase the radius of Hellish volley by 1 sqm.

2. Remove the magic resistance talent and add it to the rogue and marksman buff
This would free up 10 points early.

3. Merge multistrike with expertise talent and replace multistrike with a 15 distance talent.

Marksman:

1. Piercing shot is horrible to use in a lot of situations, I would make this Piercing Rain.
It would be the size of the current hellish volley and have a 3 second cooldown with 15% less damage this would also have a 1 second cast time.
The 300 talent would increase the damage of Piercing Rain and Hellish volley by 15%.

2. Currently if you have Raise of Pace you cannot use the taunt spell at all.
Make it so you can use it and it would take 25% of their total max mana instead of current mana.

3. Add a spell with a 45 second cooldown which would increase your dodge significantly for 3 seconds
Currently in PVP Marksman are the only class which does not have a "counter" for being focused.
Mages have mana shield, paladins have Last stand, barbs have Primal Scream and Rogues have Evasion.

Shaman:

1. Increase the damage of melody by 15-25% and make it heal party members within the damage area.
This would help with their rotation and damage during team hunts.

2. Heal friend should have a 2 second cooldown but heal 2x over a 2 second period with the first being 100% and the second 33%.
The level 300 talent would then make their second heal 100% and double the heal from melody.

3. Reduce the cooldown of Burst of speed to 2 minutes, Reduce the cooldown of Paralyze to 3 minutes.

Pyromancer:

1. Increase their damage to within 10% of what it was before the nerfs.
Currently they seem kinda weak compared to others especially in PVP

2. Currently their health steal is only 33% effective make it 66% effective.

+1.

I would add some proposals to the things above.

Enchanting;
1. With the current daily boss system it kinda forces you to have multiple level 100 characters to get ores.
Make it so you achieve an extra ore per 100 levels with a cap of 5.

Rogues;
1. Currently ruthless execution is only available when the target is below 30% hp
Adjust it so it does a % dmg of max health, this way you can use the spell no matter what the targets current hp is.

Training;
Currently it takes 8hours? to use full trainig
If you play alot you will be at 100% training for the majority of the day, make it so you can turn in 100% training for a fee once per day. It should be rewarding to put more time in rather than punishing your training.