RDM solo goals:
- Something around 4-5 levels below you so you can kill them quickly. DCs and EMs are killable for a RDM, but are too slow for how much xp they give. It's a LOT faster to kill two 50xp EPs than a single 100xp EM.
- Nothing that's at a common party camp, because making people mad is bad.
- Nothing with awful debuffs (para/petri/curse/etc) unless you want to sub whm.
- Nothing that is slashing resistant or has strong defensive buffs, because until you get refresh your sword is going to be doing most of your damage. Resting for MP takes too long to make nukes worthwhile, early on.
- Bonus: something that drops items that sell well. (ie. not lizards.)
So first you
go here or
here and look at what's available around your target level. Then if you see anything appealing there, head over and try it out.
At a glance, at 25 I'd suggest trying Crane Flys in Meriphataud. They're 18-21 and have a 40% droprate on Gausebit Grass, which is currently selling for 600g each at the AH. If you want to go up a little, Bull Dhalmels in Buburimu are 20-23 and have a bunch of drops that sell moderately.
edit: Also, THF is a pretty bad solo sub for RDM unless you're 30+ and using it for the treasure hunter bonus. Go /war for melee damage until you can get /nin, or /whm for a bigger mp pool and status removal, or /blm for MP and more dots (and eventually warp).