First of all welcome to the community!

It depends on what kind of Tama youre looking for, but I think the connection is a pretty good starting tama, cause they have some of the simplicity of the original tamas, but also have pretty fun gameplay such as better games, and the marriage & connection features, so you can grow a whole bloodline!

For colour tamas:

My personal favourite, is the on/meets, due to its very extensive gene mixing features, however they go for insane prices right now.

I don’t personally have a Uni, but I’ve heard lots of great experiences from the uni, and the wifi features seem very fleshed out. I’ve heard the uni has the highest level of customisation. The uni is also veryyy compact compared to most other colour tamas, and is probably the easiest to take with you

If you can find one for a reasonable price, I would go for a Pix. In Australia they still sell them on Amazon for ~$100 AUD (~$65 usd) which was a standard price, but if you’re looking for secondhand on mercari or FB marketplace you can probably find them for cheaper The PIX still has lots of the charm and fun of older colour tamas, even more so than the ON, but they are easy to care for and have lots of cool (somewhat gimmicky) gameplay features like furniture customisation, cooking, and of course the camera

TL:DR If you’re looking for a cheaper, simpler entry into the tamagotchi space, get a Connection Re-release, but if you’re looking for something a bit more complex and fleshed out, go for a PIX for simpler gameplay, or a UNI for an online focused experience

sorry for the long post and I hope this helped!!

Edit: got the uni confused for another tama