Have played as archer myself mostly, so im talking out from that:

Remove TP Waiving

- No, please dont, it gives us a reason to use the combos. One extra attack for free tp is great, and it is great that we have to earn it.

Reduce TP Costs

- This has already been done pretty much, tp waiving is a great way to get more tp while also being able to use other skills.

Keep enhancement of Weaponskills by Positioning

- Yeah, its a great thing, though with archer, solo 8 yards away ... not that easy really. We need to have one of them be less than 8 yards away or something, so we got something for both sitations.

Remove Positioning Requirements for Combos

- Nah, it is a part of the combo, if they remove it, it is like getting double damage without doing anything, then they could just remove tp and mana from the game instead

Increase Quantity of Combinations and Effects

- pretty sure this is being done as we speak, but remember, this game isnt ten year old, meaning it is still lots of stuff to be added.