You may also:
- Defragment the disk and enable the automatic defragmentation if you disabled it (it’s enabled by default)
- NTFS Disable 8dot3name
- disable access time: [Solved] Win10 20GB Ram Usage - #17 by arrogantrabbit
- Try to add an SSD as a tiered storage:
- Windows Tiered Storage Spaces
- software raid - Storage spaces on Windows 10 and tiering - Super User
- How to set up tiered storage on windows 10 - #8 by Aprazeth - Storage - Level1Techs Forums
- Nils Schimmelmann's Blog — Intel Smart Response Technology vs Windows 10...
And @Roxor mentioned, there is a new experimental feature for caching in the nearest release.