Couple of questions about multiplayer

While it is great if you can beat cruel AIs, the tactics you need to use to beat the Vicious and Cruel AIs are generally not the ones you need to succeed at with multiplayer. Those AIs get such a large income bonus and other cheats you basically need to abuse all of the AIs tactical weaknesses to inflict massive casualties and eventually win a war of attrition. Human players will not fall for these kind of tricks, they won't have any inherent economic advantage over you but they will use their fleet infinitely better than the AI and will gladly go for leave yourself vulnerable, even if that's only 10-20 minutes into the game.

If you've played online with other RTS games you should be able to adapt to it fairly quickly. Generally what you need to master is very fast initial expansion, situation awareness (I.e. try to keep scouting up at all times), the details of the counter system, that kind of thing.

It's always varied, but yes it's never been huge compared to say Starcraft. Most competitive RTS players think the game takes too long and the people who like longer games think standard PVP multiplayer is too fast and cutthroat, so they only play against AI (compstomps) or with friends.

Hi Scragins1,

It sounds like you've played enough vs. the AI to understand and experiment with the basics. I'd recommend reading the guides available on Steam Community by GoaFan77 (poster above) and Grimm (more advanced MP tactics). If you are used to playing RTS MP in general, know the ship counters, how to efficiently expand, which the best capital ships are and when to use their abilities, know the tech trees well, etc. then you're pretty much ready to jump in and try MP. It's really important in 5v5 games to know what to do based on your map position (the guides cover this).

It is a small community (there are usually around 200 people online) with usually just a couple 5v5 games running at any given time (and others playing private friends only games). On weekends it is busier and there might be smaller 3v3 games along with some 5v5s in progress. I'd recommend trying out a variety of any you can jump in on, including free for all (FFA) or any "Noob Only" games you can find. Those will be easier than 5v5 games, which usually have a regular crew of skilled players - but there are frequently newish players joining in on those as well. If you join a 5v5 with zero games under your belt, people will assume you are either a noob or a smurf and you may get kicked if more experienced players are waiting to join as well. It helps a lot if you have at least 20+ games played online. If you like MP RTS, I highly recommend it though. It will be challenging but it's way more fun than playing the AI and it's very satisfying to improve over time when faced with better competition. 

Welcome!  What Ekko Tek said.  It sounds like you're ready to move up.  As a general rule, if you're experienced playing other RTS games in online PvP, you should be able to pick this up pretty quickly and you'll do just fine.  Here's a link to Grimm's excellent guide:

http://steamcommunity.com/sharedfiles/filedetails/?id=161168470#-1

The Raging Amish unit guide is getting outdated, but it's worth a read, too:

https://forums.sinsofasolarempire.com/319926/page/1/#2188810