Hi Derpinator, I like the team a lot!
This is a well built team featuring an underrated mon in rotom heat. The team is overall very solid, But one concern is how it fairs against rain teams. Powerful rain hits are going to maim the team, as the only water resists have no recovery and arent bulky. The team fairs poorly vs rotom wash, especially on sand since your only water/electric resist is pursuitable. Also strong hurricanes hurt everything other than rotom heat, and even then it has a hard time taking on all those rain threats. Sun shouldnt be too big of a problem because of Latios and terrakion, so I dont see rotom heat doing too much works vs the most popular archetype atm in rain offense. I would suggest a life orb tank Latias over the scarf Latios and a scarf keldeo over the Spex one, basically reversing Latios and keldeos roles. Moreover, rain could be handled even better if you could go back to rotom wash and replace xatu with a specially defensive jirachi. This way sun is handled well (Latias, terrak, keld) and rain is checked much easier (Latias, rotom, keld, rachi) and sand as well (rak, keld, wash). Scarf latis really have a problem vs sand because they can't revenge without being pursuited. Xatu isn't the most reliable in preventing hazards especially vs stuff like terrak, tar, deo gar etc (currently gar poses quite a big threat). If you do adopt the jirachi then you can move rocks from rak to jirachi, and replace it with taunt on the former. You can also just replace the current rak with a sub salac variant.
Ps. Currently rp lando is a huge threat especially with tar, since it 2hkos heat while you are unable to ohko. That's a mon to keep in mind