Nice idea! Is there a way to specify where to insert it in the post e.g. after a specific sentence?
If you are not paying for bandwith, storage and network traffic for the site, then there is no issue in limiting the attachment size. I have however found that anything past say 2MB photo file is a bit of waste. Your included image is less than 500KB. Unless you have generally have very high quality perfectly focused photos, it does not add much. Larger files are also a bit more tricky to upload on slower connections as you might get timeouts.
