Let me throw in my very opinionated (I’m the author) choice of UI to access a restic repository: rustic snapshots -i 
This is in fact a TUI (Text User Interface) which has the following properties (some can be pros or cons depending on your point of view):
- Features: View of snapshots, trees (including file preview), diffs, statistics information; restore on any level (snapshot/tree/file), allows removal and modification of snapshots. I don’t know any UI having more functionalities to operate directly on a restic repository.
- Can be started directly on the terminal including e.g. SSH-sessions; no browser or network connection needed/supported
- Single binary without dependencies (does not even depend on a restic binary)
- All code is a re-implementation of restic in Rust and completely independent from restic
See also