One of the problems with an online-only game is making sure there are people to play with and that you can actually find a match. Right now we're seeing people join servers looking for a match, leaving immediately after only for someone else to do the same thing a few minutes later.
So we've got a few things up our sleeves to address this coming in a future update in the next week or two:
Improved matchmaking logic
We've changed the matchmaking logic to make it more likely that players will get matched up. It now allows more time for more servers to report their status before players are placed on a server rather than giving too much priority to those that simply happen to respond the fastest. The nature of Kaboom! makes it comparatively latency tolerant. You can still have a great time with up to 150ms of latency which is far better than not being in a match at all. Obviously the system will prefer lower latency but it'll pick something else in a pinch.
Drop-in Matches
Right now you can't join a match that's in progress, this will be changing so that you can join a match at any time. Obviously this won't apply to ranked matches down the line when we have them. This will also be paired with the new bots (see below) to maintain a minimum population in a match so you've got something to do.
AI Powered Bots
Bots will give you some semi-competent opposition to play against while you're waiting for a match. These bots are powered by high end machine learning systems that will be continually trained and improved over time.
Minimise and alert
If playing with bots isn't your thing, the other option we'll be adding will let the game minimise to the taskbar and run quietly in the background. Once more human players show up it'll notify you so you can continue playing.
Scheduled play times
We're also going to have regular scheduled match times that we'll be announcing in-game, on Steam and in Discord to encourage people to play at similar times to improve the odds of there being populated, natural matches.
In the mean while, I'd encourage everyone to join the Kaboom! discord server ( https://discord.gg/vewSfBDj8C ) and find matches in your region that way :) Thanks to everyone who has joined us in early-access so far and it's great to see you enjoying it!