New summoner spell

What are the 2 least used summoner spells on summoners rift? &, I think with a little bit of balancing they could easily combine these 2 spells into one making it actually useful, because both these spells on their own are useless in 99.99% of games.

This would also give a variety from heal bot lane, whether you want to really protect yourself, or be a team player with the heal, because barrier on adcs is 100% useless atm, and the the only champion who ever uses it is lux. Overall I think if they played with the shield value and cd, they could make this a legitmate summoner spell that is useful without being too overpowered.