Small breed health comparisons?

Hi! I’ve been really having my heart set on getting a cavalier King Charles spaniel, I’ve met many and they are just so perfect. I love how calm and gentle and loving they are.

But as I’ve started doing more serious research I’m starting to worry about getting a dog prone to so many health issues as I’m not sure I can handle a loss so early on

I’m still considering them but I want to think about some other options and meet with different breeders/dog owners

I’ve been recommended to look into these breeds:

Havanese

Maltese

Shih-tzu

Bichon frise

Coton du tulear

Can anyone tell me about them? What kind of health issues do they have? Which is healthiest? Which is the calmest? Is there one you’d recommend way over the others?

I’m really looking for a small dog I can easily travel with who is a cuddly Velcro dog. I’m not a first time dog owner, and I’m prepared to work with a trainer, but I am tired and have some health conditions and it would be best if they’re an easier to train companion dog (eg not a working dog)

Im posting this to ask for breed advice only! Please don’t only suggest to adopt and not shop. There is a chance I’ll be able to adopt (shelters are typically very empty where I live) but shelter dogs still have breeds and I want to make sure I don’t make any mistakes in who I end up bringing home

Sorry if this is long and hard to understand. Thank you so much to anyone who helps!