The whole reason Velt died off after re-releasing is due to one thing, the anti-cheat. So many people were getting fed up with getting false banned and having to wait 1-3 days to get unbanned, some of which were not able to as they had no proof or recording. As a result, the player count went down at an alarming rate.
My suggestion is to completely disable the anti-cheat from HCF/Practice, similar to what Viper has done. And instead, just have logs of players appear for staff and admin, and allow them to freeze/ss the player themselves and not rely on the anti-cheat.
This way the forums won't be flooded with things such as "false ban", "ban appeals" , etc.. However, on top of doing this, Velt would need to create a big event that would gather people to the server and allow them to experience playing on it without the anti-cheat and false bans. To do this they would probably have to do something to revive the HCF present, such as F TOP payouts or something else interesting.
When Velt first re-released it was easily the biggest HCF server for around 3 months, but died out due to the anti-cheat. Removing the anti-cheat like other big servers such as Viper has done would surely boost the player count.
I hope you guys take this into consideration and make Velt the popular server that it once was.