I would advise a druid myself, as I'm doing a game as a human Druid with a Tifling Ninja, two man trucking most of ROTRL with my sentient, armored, scythe using T-rex companion. Totally legal, I swear.
For you'r rolls, I would say. 13 Str, 16 Dex, 16 Con, 15 Int, 18 Wis, 14 Cha. As human. Dwarf, Half Elf or Half Orc would also work, but not be as flexible feat wise.
If your GM allows featured races, Aasimar can be optimized to do most anything beautifully, as can Tiflings to a lesser degree. Tengu are also fun, especially if you get an elf curved blade (scimitar crit range with d10s) as long as you don't mind being a bird.
What you want to set yourself up as is a support caster, one part healer, one part buffer, one part debuffer and one pert magic item maker. The range of druid spells and relatively few feats needed to be effective makes it very easy to fill all these rolls (ROTRL gold starves you, so the ability to make your own magic items at 1/2 price effectively doubles your party wealth).
The big key for this one is your animal companion. I like the T-rex because, well, its a T-rex and has one massive bite attack with monster stats at the cost of teny tiny arms. But most dinosaurs or other combat focused companions, such as big cats, wolfs or trents, will do just fine. Animal companions progress nicely on their own, but they become much, much more effective when you give them items, such as armor. An armored dinosaur is all but impossible to hit with mooks and makes a wonderful meat wall and flanking partner for your dex based team mates.
In addition I would suggest improving the anamal's Int with the level up stat boosts. While a few points in dex, str or con is nice, putting those points into int allows you to actually talk with your companion, removing the limitation of tricks (Albeit only simple instructions as int 3 is still rather dumb). In addition, it lets you give them any feat they like rather than just the animal ones (My rex has weapon prof scythe for example) and lets them advance their skills like any PC would (Still likely 1 per level as they have sad int scores).
Finally, there are two spells that I have found all but essential in this endeavor. http://www.d20pfsrd.com/magic/all-spells/a/atavism gives the advanced creature template which is a massive buff that improves every aspect of your companion. The arguably more important one, depending on you companion, is http://www.d20pfsrd.com/magic/all-spells/a/anthropomorphic-animal . This not only lets your companion talk, but also lets them use shields, weapons, doors, cheaper armor and and most other tools while retaining the ability to use a fair number of their natural attacks. Even better as the effect can be made permanent for 7500 should you find a level 11 caster with the permanency spell.
