Paraiba is a win for me. 
Rubillite is also beautiful but on a personal note, I've noticed that while I love burgundy and buy/have ruby jewelry, I actually tend to wear my blue-toned stone jewelry more lol.
Tiffany is a bit boring and generic? It's a nice floral design but I'm sure you can go to your local jeweler and find one that is very similar. It is definitely more everyday/wearable and probably will go better with more occasions and outfits.
However, this is saying from a perspective of a person who already has a collection of Tiffany, Cartier, Bvlgari, Chanel fine jewelry rings, and has moved on to things that I would find a little more unique and special.
Just something to think about.

Rubillite is also beautiful but on a personal note, I've noticed that while I love burgundy and buy/have ruby jewelry, I actually tend to wear my blue-toned stone jewelry more lol.
Tiffany is a bit boring and generic? It's a nice floral design but I'm sure you can go to your local jeweler and find one that is very similar. It is definitely more everyday/wearable and probably will go better with more occasions and outfits.
However, this is saying from a perspective of a person who already has a collection of Tiffany, Cartier, Bvlgari, Chanel fine jewelry rings, and has moved on to things that I would find a little more unique and special.

Just something to think about.