Networking
Currently cast server update's player data around 10 packets per second, you should increase even though it would increase bandwith.
Add cooldown checks for packets that normally can't be sent that fast, make sure to have checks against players with huge ping.
More serversided/clientsided checks for packets that normally aren't possible to be sent from current's player state(seems it's still possible to exploit them).
I highly suggest a total rework of cast-main servers communications regarding Host,players,priority of packets regarding being host. Host should be able only to control room related settings and manually kicking players while the game hasn't started yet. By rework I mean calculating damage and everything serversided and not letting the host player take care of that since it can be easily manipulated and exploited including possible threats to other players(talking about how cast server broadcasts the message to every player).
Game's Data/Resources Loading
I'm pretty sure you guys are aware of how items are structured in cgd, let's take example how they used to add a weapon:
2 hours, 1,7,30,90 day(s) -> 5 fields
Then 1 field for unlimited version non upgraded.
3 upgrades in total and 9 fields for each level in total 27 fields for all upgrades
If we sum all this up 33 fields in most scenarios just for one weapon in itemweaponsinfo.cdb, take consideration there's alot more items in the game than this.
Improve textures,sounds,maps loading times and rework the caching system.
Client
Previous clients had tons of memory leaks and bugs, but I did noticed you guys did improve already on taking care of memory leaks which is very good.
Currently the game doesn't use atleast 1080p textures in 2022 for background images atleast they are just stretched as every visual resource in the game, and yes you guys are limited alot by memory bandwith usage due of the game being x86. (optional)
I would suggest if you guys really won't change your decision related to XignCode anticheat, atleast make sure you guys manage to get atleast latest version updated of it and the full version, not some old version that doesn't have many client sided checks or even heartbeat system some of them. And I strongly advise to also guard/checksum checks or more by yourself and not relay entirely just on XignCode.
People might wonder why they have lagg sometimes even with high-end pc on 8v8 matches or 16 players ffa, well that's because of the iteration system in the game the more updated/rendered objects in the game the slower the game gets. It needs completly rework and optimised.
Once you master gamebryo, please do fix player's camera collision bugs being able to see through map from specific angles, same goes for weapons/effects/glow being visible through walls and other spots. Including glitches through maps.
Features
Add demo system, and make sure to be able to see every player's perspective exactly 1:1 like you would watch from behind him his entire aim movement,crosshair placement,fov,zoom in for sniper,animations, every effects in the game, basically everything the player sees in the game when normally they play, and being able to control and see from every player's perspective in match, slow down to see the demo per frames etc.. Also remember this is not only useful against cheaters and to calm down community's suspicious regarding some players or staff, but can be a big step for the game and streamers,youtubers,editors who want to make nice and cool edits. For editors I would suggest adding posibility to remove objects/sky, make sky green to be used as greenscreen for editors would be ton of help and would be much appreciated by entire community for sure.
Being able to disable glow/effects of items from other players other than yourself(visual only).
Add more video settings that could improve fps for players by lowering them.
Add support for most text encodings in chat for example: being able to see arabic,cyrillic characters and such on from same client to allow other players to communicate as they like.(optional)
Add support for copy/paste controls from chat, but remember to add checks against spamming and such on.(optional)
Add social community animations/emotions that would be usable in any game mode while playing, for example kissing, saluting, laughing, crying, stuff like this were once implemented in 2013 in plaza version.
Regarding trade if ever implemented again, don't make it p2w, you guys could make some sort of monthly pass access for trade that can be purchased by either some good ammount of mp earned from game, or bought with real money, let free to play players enjoy this as well.