I, too, love my Magic Mouse, but it seems it's not the right fit for OP.
Sorry - guess I can't read
I found that you have to adopt a different style with the magic mouse. Lightly grip it with your thumb on one side and your ring and pinky on the other. Its easy enough to slide around then and you can use your index finger to slide up and down the surface for scrolling. Don't try to use a death grip like with those large mice from MS that you hold more like a ball in your hand
I found that asking others for a recommendation on a mouse is pointless.
Every ones hand is different, the way they hold the mouse is different - what might be a very comfortable mouse to use for one can be totally useless for the next person.
When I need a new mouse that I'm going to use regularly and a lot, I go to Stables or Future Shop or Best Buy and hold each one they have on display to see how it feels.
The ones that feel good to me, and there are usually very few, I then check out on the net a bit more.
The last really good mouse for me was a Logitech MX510. It's quite big but fits my hands perfectly.
I actually scouted around to get a few more long after Logitech discontinued them simply because I liked them that much and I had a few Macs I wanted to use them on.
OP says he liked the Mighty Mouse - that is still available, just not from Apple.
For a MacBook I would also go for a BT mouse simple because USB ports are at a premium. No point buying a wireless mouse with a dongle - might as well buy a wired mouse with its advantages.
I ended up getting the Logitech M705 with the USB receiver like pm-r suggested. It was priced at 23.99 ($6 off the regular $29.99) at Costco, so if you bought one recently, you might want to go back.
I'm quite satisfied because it aligns perfectly with my old wired Mighty Mouse. It has the side button (which I use to view the desktop) and also the scroll bar button (I use to see all app windows). It's actually better than the MM because it has back/forward buttons! Of course, I do use up valuable USB slots (only one left with the mouse plugged in), but that's not really a problem for me. It's not often I have to plug in more than one device anyways. I'm sure there's a mouse like what I described out there with Bluetooth, but I don't think it would be at this price.
krs - you mentioned that you could buy a Mighty Mouse not from Apple. From where (assuming new)?
iMac Aluminum 20"
MacBook Pro 15"