from experience it's better to have a pure melee build so you don't have to recharge spells because you will get constantly invaded so you wont be able to use the bonfire between fights, of course you can reset but you lose a eod. alsso make sure you have the right of kindling so you have 20 estus and get them to +7.
High traffic area. So I suggest places like Undead Parish, Blighttown, Sen's Fortress, Anor Londo Oolacile Township... you know, areas with lots of popularity for PVP.
I wasn't very impressed with the GL miracles when I tried them, but that's just my personal opinion. But if you want to fit the theme, then yeah, perhaps you should use them.