Just too be clear this is MY opinion and in the end, the choice of your team is ultimately up to you. For raids you will want to have light keeper as offence and tank, walla Walla for healing, sas for tank (if you need an extra tank), grim feint is also a good tank for offence, ronnin is a great hero for raids and offence and anubis is great for raids. For defence (offline play and guild wars defence) I would suggest putting light keeper on the base along with Walla Walla, phobos who is great at defence, gunslinger, sasquach as a tank and ronnin. For guild wars on offence ronnin, dread drake to destroy the base, walla walla, light keeper, anubis as a sniper plus sniper aid against troops and sasquach. For team events (team here be monster+team dungeons) use either Walla Walla or gohlem as a healer, gunslinger for you he wayflyers to deal more damage, pumpkin duke for the speed boost, trixy treats for the same reason as gunslinger and trentar(if no one else on your team has him). Also skull knight and Michael aren't bad but they are only good when they proc so they could be good in offence and I know creation is good in lost land .I do not know about the Dragon you have but I know many people on this forum can help you with him. As I stated who you use is ultimately your responsibility but I would suggest messing around with different heroes and teams until you find what fits but this is my suggestion
will focus the resources on the following hero:
- dove keeper
- ronin (if you focus on base attack on gild war)
For sas I will wait to see if you can get lazu or cosmo in the near future...