I make an UI comparation that maybe used by Proxmox developers to expand its features:
| Proxmox | OWP | |
| Support KVM | Yes | No |
| Support OpenVZ | Yes | Yes |
| Show IP Address | No | Yes |
| Able to set expired date | No | Yes (this feature very usable for Hosting companies which sale VPS on time based) |
| Remember me on Login | No | Yes (very usable when you manage many Promox from 1 dedicated IP) |
| Template for installation from URL | No | Yes |
| Add user define Description to VPS Guest | No | Yes |
| Select owner/permission when create VPS Guest (on Proxmox you only can select Permission after VPS created) | No | Yes |
| Reinstall VPS | No | Yes (absolutely useful for hosting company which sale large number of VPS) |
| CPU Limit (Proxmox only able to set CPU Units) | No | Yes (help you avoid client eating all resources) |
| Change VPS Limits (Proxmox only show the Limits but not allow to edit) | No | Yest (very usefull for advanced user rather than edit config file manually and of course you see it directly) |
| Show RAM and Disk Usage in MB (Proxmox only able to show in % format) | No | Yes (very useful if you allow Oversale HDD and RAM) |