No need to throw them away - they’re a pair of decent archers. Sure, maybe they’re not quite as good as say Relic Hunters, but they’re still pretty decent - for starters they have one of the highest base Accuracy stats of any thrall, which helps close the gap between their DamageModifierRanged and that of those that are ‘better’.
Sure, if you really feel the need to have the ‘absolute best’ thralls, then you’ll need to search for them (and get yourself involved in the endless arguments over which is actually ‘the best’ ) - but you can still complete endgame content with ‘lesser’ thralls. T4 exiles, Darfari, Black Hand - they can all be enough, they just might require a bit more protection from you in some fights because they’re maybe slower to get the kill or just have lower hp. But stick them in some endgame heavy armour and they’ll still survive most things without breaking a sweat. I’ve said it before and I’ll say it again, my favourite thralls in the Exiled Lands are t3 bearers - they hit like a wet noodle, but have lots of HP and in endgame armour can pretty much withstand a direct nuke. You don’t need the best, you’re the hero