Kyrou already signed an 8-year extension. I also don't expect that GMs from around the league will be eager to sign a retaliatory offer sheet because of what transpired last summer (aside from maybe the Oilers front office). However, with McDavid and Bouchard needing extensions, the time for retaliation is not this offseason.
The only current RFA the Blues have going into next season is G Joel Hofer. I expect Blues would easily match anything up to the second round compensation price. Anything higher and the Blues probably opt to not match and take the offer sheet compensation. I could see Hofer as a potential offer sheet candidate this offseason. But short of the Blues signing Binnington to an extension which is entirely possible, Hofer is slated to be the next starter with the transition occurring over the next 2 seasons.