Climbing will almost always be better on a HT, especially if that’s what you’re used to. More hang ups, but more raw power.
FWIW, I got a full suss after riding a mates in Wales for a day. Since then, about 4 months, I have taken the hardtail down more decents that I got the Full Suss for. Keep the hardtail. It’s more fun HT. Plus! It makes you look like the pirate spawn of the Hoff and Steve McQueen at the end of a trail.. But without the misogyny.