Which is why I suggest an alternative set of sounds to use to widen the library.
Why not use both? They both are impressive in their own right.
Also, if you want to get into some FM emulation, I recommend the program TFM Music Maker, a free tracker-program made by Russian programmer Shiru. It's pretty good, and although it takes some doing to learn how to use, it is free after all, and some of the results can be pretty good if you know what you're doing. Listen to the examples and see if that's the direction you wanna go in.
Examples:
Something I made in TFM MM (lul self-plug)
One of the most awesome things your ears will ever hear (aka the Robocop III theme from the Commodore 64... IMPROVED WITH BLAST PROCESSING)
^^^^ LISTEN TO THIS LAST ONE^^^^
Of course, a downside is that the drums lack that meaty super-punch that GeckoYamori et all's stuff contains with their work, but it is a highly affordable alternative and it's pretty fun to use, to boot. It does offer the possibility of making your own FM synths, but that's hard to do (but not impossible- I've done it with lots of experimentation). The presets it DOES come with are pretty sweet though, and can be tweaked themselves. Of course, since it's a Genesis tracker, it only allows up to 6 tracks at once, but that's not too much a problem.