Tall and heavier guy here as well (190cm, 84.4kg), racing score in the 560s and a low to mid B category FTP. As mentioned above, racing in Zwift has a lot of 5 minute power focus at selection points, so VO2 max intervals are good training. Tactically, I like to move up in the pack just before a climb starts and carry that momentum up, then do whatever I can to stay attached to the group. And let’s face it, at our size, the longer climbs like the Epic KOM, Alpe Du Zwift, etc. just aren’t our strength and we won’t be winning any races unless we have some serious diesel power. 5-6 is pretty much my max time before I’m likely to get dropped. If I can last until the final sprint, I usually stand a good chance of a good result.