feat(docs/roadmap): update (#6150)

Co-authored-by: Jon Sands <fohdeesha@gmail.com>

docs/roadmap.md

@@ -1,13 +1,40 @@
 # Roadmap
 
-> Our roadmap is very flexible - you can check the **milestones** repository for a complete overview of all the features we are currently working on.
+The goal of this document is to give you a hint of what's next. However since all topics are very complex, there's no specific order or target date.
 
-## Features
+## In tech preview
 
-- [Milestones](https://github.com/vatesfr/xen-orchestra/milestones)
-- [Alerts and reports](alerts.md)
+This means some parts of the following features are already available, but only partially.
 
-## Fixes
+- [XO Lite](https://xcp-ng.org/forum/topic/5018/xo-lite-building-an-embedded-ui-in-xcp-ng): a small/light version of Xen Orchestra bundled inside your XCP-ng host.
+- [Public REST API](https://github.com/vatesfr/xen-orchestra/blob/master/packages/xo-server/docs/rest-api.md)
 
-- [Known bugs](https://github.com/vatesfr/xen-orchestra/issues?q=is%3Aopen+is%3Aissue+label%3A%22type%3A+bug%22)
-- [Enhancement requests](https://github.com/vatesfr/xen-orchestra/issues?q=is%3Aopen+is%3Aissue+label%3A%22type%3A+enhancement%22)
+## In progress
+
+Items in this list are already undergoing development, but are not yet available to test.
+
+- [XO 6](https://xen-orchestra.com/blog/devblog-3-working-on-xo-6/): a large revamp of Xen Orchestra: improved speed, security, lazy loading, XO tasks, a brand new UI and much more!
+- Auto backup validation: a special "auto restore" task to check if VM backups are bootable
+- OVA export
+- Individual VDI restore
+
+## In design/PoC phase
+
+This is the initial concept phase, where we discuss the general approach and how to make the feature real.
+
+- Block based backup (NBD): using NBD as the backend to export VMs. Faster and allows fun features, like compression and dedup.
+- XO Resource scheduler: improvement of the existing XO load balancer
+- Fetch Netbox to display available IPs
+- Packer plugin for XO API
+
+## Backlog
+
+A short non-ordered list of interesting features or ideas to develop eventually.
+
+- Improve XO proxies for complete XAPI reverse role
+- Container as first class citizen: allow container management/creation/cycle from XO
+- k8s integration: improving integration with Kubernetes inside Xen Orchestra
+- Upload ISOs to NFS ISO SR via XO (XAPI modification likely required)
+- Health check smart service from xen-orchestra.com
+- Geo/Async backup
+- Native backup encryption