I think the #1 problem is too many tools. For instance, I have collaborated with people using Skype, Discord, WebEx, Slack, IRC, Facebook Messenger, Microsoft Lync, icq, AOL Instant Messenger, Paltalk, Tivejo, Go To Meeting, etc. People will tell you horror stories about all of those things, but I have found them all to be adequate. Often people conflate problems with their audio and network with problems in the tool…
I was going to make the same point. If there was a (preferably web based) chat / call / video conference app that allows me to connect to all of those services and never have to keep context switching, it would be a big improvement. Maybe there is one and I just don't know about it? As far as issue tracking, unfortunately I think the functionality and workflow differs too much between products for there to be one UI…
It's only 4 MB and handles tens of thousands of Slack messages in one chat without lag.