1. Any gearing should be fine, when you're used enough to a kind of "attack, read and evade" offensive system in PvE. (Though there are times the enemy's attack covers a different area than what you'd see.)
But if you really prefer having a reliable gearing, you might want to try to get a Set from a Mission Map's "Gada reward" of your level range (either Lv.27 or Lv.34 Set). "Gada rewards" can also be found as one of the three Equipments randomly given, as you might have noticed.
Eventually, since going up until around 48 is quite fast, you might rather want the Lv.35 Anukus Set found in the Lv.35 Underground Graveyard's "end reward".
2. At your level, the Lv.27 Water Spirit Weapon you can get from a Quest after completing the Water Spirit's Quest series.
Again, because going up is easy, you might want to try to get the Lv.37 Dark Soul Weapon, in the Spectres' Tower (either from "end reward" of crafting after getting the Recipe). But DSW repairing cost is like around 5~6.4 times the WSW (respectively approx' 4~6.4g and less than 1g).
3. Well, yes, Silver Coins. And there isn't really a "best place", because of the current system, other than any place in which enemies have 5 levels more than you.
In your current case, it makes Alvida's and Artis's Maps your "best places" for a short while. If you want to have both Silver and Gada, rather have fun outside of them, or in the Water Temple's crowded areas.
4. I'll let other people answer it.
Edited by Rainnowx, 02 December 2016 - 10:32 AM.