Upload & Sell: Off
1) You might look for a used Sigma 10-20 f/4-5.6. I owned one for quite a while, before I got their 12-24 for FF use. They also have a newer, fixed-aperture version, but new or used it will be more pricey.
2) You've got the latest firmware.
3) You can reset the file number to zero. Select File Numbering from the menu, then Auto Reset, rather than Continuous. Whenever you format the card, it will start from zero. I've never reset mine, and it's at 8972 clicks right now.
4) No way to get an accurate shutter count with third-party software.
FWIW, I still shoot with my 10D all the time, and I'll never sell it, even though I've also got a 1Ds2 and 1D2n. Some of my best prints are from the 10D, and as far as the xxD bodies go, I think the 10D had the best image quality until the 40D surpassed it. If you nail the exposure correctly, the 10D isn't as noisy as the 20D/30D, and it's got those rich, saturated colors from the older D30/D60 and newer 5D bodies. And, there's that lovely, muted shutter sound. Still a great camera, and worthy of the best glass you can afford.