Look, for ur builds, let's discuss the first one,
the bow:- Bows can tank some damage and the KB skills are very usefull.
- You said you will add 20 cold, which is very nice, because snow is very usefull when ur in trouble.
- Ranged attacks (like Tasdik also mensioned).
- Bow + crit = deadly
Second build, the nuker:- Extremely cool to grind with, the nukes keep me amused, and it grinds very fast.
- Fire/cold ftw, because it's proven that fire nukes are the strongest, and with the fire embue, they rly rock + u have the flame body series, which increase ur bicheon hits.
- The fire build contains the Fire shield series, good to become immune.
- Disadvantage:No speed ffs T__T
- Nuker has another disadvantage (this is rly stupid in the nuker build): When u pvp, you can't do anything without snow shield, so when u got killed after you casted snow, you need to wait 2 (?) or three (?) minutes to cast it again, before you can pvp and tank a bit.
- Btw, Nuker with ice has better phy defence

Hoped I helped, GL