I plan on combining www.athas.org, the May issues, & anything else I come accross. I'll pick and choose what I like best
That won't be necessary - IMC the typical thri-kreen NPC has 4 levels of ranger. They live in a harsh environment, so it's not unusual they would gain levels. They end up with 6 HD (the right number) but are also flexible, just in case you wanted to give them cleric or psion levels instead.Thri-kreen is another race that is problematic to convert, because quite frankly they were overpowered in 2e. Defining traits are: alien mindset, non-humanoid, multi-armed, thick chitin exoskeleton, less need of water. They will either need to be reduced in power, or be given a level adjustment. One solution might be racial levels, as in Arcana Unearthed. That would also explain the differences between a starting PC thri-kreen and a “monster” thri-kreen – the “monster” is simply one that only has racial levels. Worth thinking about.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.