All clubs of our size will lose good players - it's going to be basically a revolving door, losing the best guys after 1-2 seasons.
As St Johnstone have found, and we did to a lesser extent this summer, you need to be on the front foot almost constantly to ensure you're proactively replacing these guys. We failed to replace Connolly and Durmus, and hoped that sticking with our 3-5-2 would paper over the cracks. We have just about got away with having one flawed transfer window, and at least we've made amends with Jones, Greive and Gogic.
As Lex says, we are safe now and I would imagine we're starting to line up replacements for the guys who'll be away.