The cruel AI is pretty tough.  I've been splitting 1v1 games about 50-50 with them lately.  The trick to being competitive with them is you really have to focus on using the tactical advantage(s) of the race you are playing.
TR - Get Truce among Rogues immediately and blitz colonize your area of the map.  Then quickly roll out the Ragnarov Titan.
TL - Sprint to Novaliths and build 4 as quickly as possible.  Then bomb the enemy with them while fortifying a nearby choke point.
AR - Rush the Eratica Titan and get your Mothership to level 5 with 3 levels of Malice.  Use Chastic Burst + Malice to clobber the enemy fleets.  You can also set a trap for the AI with Wail of the Sacrificed.  Meteor Storm and Shield Bestowal also can help you defend a choke point.
AL - Your only hope here is a well built choke point with Meteor Storm and Shield Bestowal + the Coronata Titan with Suppression and Subjugating Assault.
VR - Titan + Mobile Orkie.  Use the Titan to kill frigates and the fully upgraded Orkie to kill everything else.
VL - Rush Stripped to the Core.  If you focus on it, you can have this tech in around 20 minutes.  Then colonize and strip every planet beyond your homeworld and asteroid + dwarf planet.  Use the resources to build several additional capital ships and then a huge attack fleet.