I wouldn't say that's a lot, especially for a Desire. I have more than that on an unrooted G1 and it works absolutely fine, although I do wish it had more space for games. The Desire has over 5x as much RAM, so you should be able to store 200 to 300 apps on a Desire without having to root and using Apps2SD. Apps2SD comes into it's own if you want to have an absolutely obscene amount of apps, or if you have an older phone with far less storage.