Coming from someone using an S7 Edge since its release, I don't think it would be an upgrade for me. I'm losing more than I'm gaining, I don't think I can go back to a non-waterproof/water-resistant phone which doesn't have wireless charging.
From an S6Edge+ perspective, if you're missing out the latest software updates and need an upgrade in the camera department, then go for it. Otherwise, there may be a better choices in the market or just go with a "premium" smartphone to future-proof for another 3-5 years.