You cannot beat Yahama guitars for the low end market in all honesty. They really have nailed almost all of their low end range to be superior to anything anyone else produced.
Look at the reviews for the FG700S (Solid Stika Top - Mahog back/sides). YouTube has plenty of examples of how it sounds.
There is also the 720,730,740 and 750 models, which are all priced pretty similarly, but have slightly different wood tones depending on what you prefer. I think some of them have been discontinued, but you will need to check what you can get your hands on.
Rosewood and Mahog are the most common materials used for the back and sides and you cant go wrong with either. I find mahog tends to sound better with cheaper guitars, because high end rosewood is very expensive, but mahog not so much, so you tend to get a slightly better 'value' in my opinion, but of course it depends on what you like.
The 700 Series is one of the best value purchases you can get. I would also recommend upgrading the saddle, and bridge pins to bone or FMI. This is super easy to arrange with a local luthier, and would really add more body and sustain to the overall sound. If you could afford to upgrade the nut and get some really decent tuning heads, it would be even better, but slightly more costly. Keep a decent set of strings on it (like Elixirs) which will last you weeks, if not months and keep a very nice lively tone. Any guitar with old cheap strings doesn't project the sound that it was intended for, so don't skimp.