I'm going to make a different recommendation than Jim. Take at look at the Canon SX130. It lists for about $250, but you might find it for a bit less somewhere.
Why this camera? Probably the biggest reason is that you are already familiar with the Canon menu system. It's a plus to not have to learn a new camera setup. But, Canon is still a solid performer in terms of image quality, and this camera is no exception.
Unfortunately there is no camera that will give you all you want.
* Optical Viewfinder: Pretty much a thing of the past now, although some of the higher end p&s cameras still have one, you just pay a lot more.
* Nice and sharp: Fortunately most cameras from the top brands (Canon, Nikon, Sony, etc.) will do this. As a note: zooming is better than cropping, even if only in regards to metering capability.
* AA batteries: Still several options available. The newer cameras in the same series as your A540 are using the Li-Ion batteries now. Li-Ion do provide for longer battery life, faster flash recycle times, and better response times in general though.
* Image stabilization: Pretty much standard on most cameras now. Pay careful attention at some of the lower end cameras, especially Nikon.
* Wide-angle lens: Again, this is becoming more standard. Many camera had an equivalent of a 35-38mm lens at the wide end, but many are now offering an equivalent of 28mm, or even wider.
* Timer: All cameras have this.
* Faster recovery time: Certainly improved over the years - usually a flash issue, see comments about batteries.
* Night pictures: Cameras have gotten better at this, but no p&s camera is going to do a "great" job at it.
Your comment about the color options is great. You definitely can do all of things, and more, on the computer. I see them as what I call "gimmick features". Sure, they look nice, but are unnecessary. I always recommend to shoot at the highest resolution and in normal color. You can also lower resolution and change to b&w, sepia, etc. later, but you can't do the opposite with any sort of success.
So, in conclusion, welcome to the Zo. I hope that this helps you out a bit. Just as some background, I worked at a camera store for 10 years, so I hope that I haven't given you more information than what you really wanted.
There are two types of photographers, those that shoot Canon & those that wish they could.