In my opinion, get rid of Reflect. There are much better Pokemon to set Reflect up, and Latios, with its monsterous 130 Special Attack and great 100 Speed means it should be maximizing its offensive potential. Surf and Thunderbolt are decent coverage options, especially in the competitive scene, but even if you're only considering a playthrough, running four powerful attacks on a fast and strong Pokemon should give you a good time. In competitive Pokemon, Reflect (and by extension, Light Screen) should be set up by a dedicated Pokemon; examples include Parting Shot Grimmsnarl and U-Turn Tapu Koko, who can both set up screens and pivot their teammates in. Just as a side note, I do recommend Dragon Pulse in a playthrough and Draco Meteor in competitive. Dragon Pulse is much more spammable (and honestly not a lot is taking a Latios DPulse in a playthrough anyways), and Latios can best utilize its Special Attack with Draco Meteor, landing crucial KOs on certain Pokemon that DPulse may struggle with.
Also, regarding Speed freaks comment that Psychic is stronger than Luster Purge, that is no longer the case in generation 9, so feel free to spam the newly buffed Luster Purge.
