New in the mod and the crossbow

[Kratos]

Hello, i just started playing NI and i picked up crossbowman as a class. why? archery is not my style , commando is unnecessary , skirmisher is so easy! So yes, i checked the forums aswell, read all the suggestions as xbowman, but i still have some questions like , "how much will it take for me to reach tier 4 as xbowman?"  and "should i take the best gear until i reach tier 4?" "should i become a medic or engi?"

cheers