I think that adding Simple Voice Chat and integrating it with GregTech would add interesting multiplayer challenges. My idea is that Simple Voice Chat would be added and non-creative mode voice and text chat would be proximity based, so you wouldn't be able to hear or see messages from other people if you are too far away. How far away your voice/text reaches would be increased via 2 methods: Loudspeakers and Radios, both can be put into a baubles stot. You can get a Loudspeaker as soon as you get bronze, and making it out of better metals like iron would increase the amount of blocks that your voice can reach. An electric one would be even better. A Radio can be gotten as soon as LV, and if any players have a Radio and are in range, then they can hear each other. Also, if someone with a for example, someone with an MV Radio is talking, then someone with a lower tier of Radio can still hear them, but if the MV radio is out of range of the LV one, then the person with the MV Radio can't hear the person with the LV one. In the server configs, you would be able to change if Radios are set to Private or Public. Private means people can only speak to people that they are connected to, like a phone call, and in Public mode, radios will function like a normal Radio, where everyone in range can hear you unless you have an upgraded version with encryption like an enigma. This could eventually be expanded upon and cracking encryption would be a thing. I think this is a good idea as in real life the outcome of a lot of conflicts were decided by being able to exchange information. Ultra long distance communication could be made by using satellites when the space update comes out. For early game, people could use telegraph wires to communicate or hook up to radio towers far away to broadcast their voice there or recieve info. It would be a good idea to integrate this entire system with OpenComputers. Finally, the Radio should be able to be fitted in the Terminal item.

I've got another idea: Jammers. Jammers work by using electricity to jam radio signals in an area. They would exist as items and multiblocks like radio towers. Obviously, the multiblock would be more powerful. They would have a whitelist or a blacklist for who or what to jam. Higher voltages are more resistant to jamming. For example, an LV item jammer can jam LV radios in a large area, LV radio towers in a medium area, MV radios in a small area, and not be able to jam anything more powerful. Using higher voltages like HV to jam someone using lower ones like LV would be able to jam a higher radius. Essentially, the higher the jammer's voltage compared to the sender or reciever being jammed, the more distance it can jam.