I would vote v3 out of the ones you've listed
They are on the simpler side of the later Connection versions, but still have enough features to keep you entertained.
I've heard v2 is awesome, as well, but I've honestly yet to get one!
i'd recommend against the Angelgotch as I've not been too impressed. I own two, and have given one away (well, to someone who will 100% give it back!) and they don't like it either. It's easy, somewhat boring, and the button input lags. The characters are cute, though - and animations, as well. I just prefer a more responsive Tama.
I can't say for the Devilgotch, and my Mesu/Osu pair are still packaged
Although they seem cute.
The angels don't all have that input lag, mine doesn't have that at all. It's more responsive than all my p1/p2's.
So wouldn't make a decision based on that alone

Angel is one of my favourites to run when I have less time to check it. You can find an angel for 30-40$
Osu/Mesu are really fun too, they have the simplicity of a p1/p2 but with loads of characters you can obtain if you run them more than 1 generation. You can find those relatively cheap too, for about 40-60$ for the two.
And for the Devilgotch, I would say it's only worth it when you're a collector. It's cool but then again not that special to be paying 500$ for it if you just want a tama for fun and running it.
That's for the vintages. These can go from 350$ and up depending on the shell.
The Morino and Mothra are but very fun too, are much alike only the mothra has a much faster cocoon stage. The Mothra needs discipline when he tries to attack the city and the Morino you need to keep safe from being stepped on and frogs.
These will cost around 40-50$.
But I see you have many of the color versions and you're enjoying those alot, I might recommend the new Tamagotchi P because I have the feeling that the vintage models might bore you.
The V2 and V3 are nice too but they lean more towards the vintage pets, has some new features like the gotchipoints and shops but nothing more

These are quite cheap too, 15-20$ for one.
Hope this helps!
Edited by Stefke2108, 27 September 2012 - 06:24 AM.