Please work with your account manager for any roadmap discussions, as roadmaps are considered NDA materials.
ENS 10 is the successor to VSE. Essentially, ENS 10 is VSE/HIPS/SiteAdvisor in one platform. Each module in ENS 10 is not a direct analog to VSE/HIPS/SiteAdvisor, but there are a ton of new features and improvements. I'd strongly suggest trying out ENS 10.1, or if you want to see what's coming next, ENS 10.2 is available for beta testing.
ENS does not replace ePO. ePO is the management console, ENS and VSE are point products managed via ePO.