Actually, it's possible to make traits that inject into the Rewards Store without conflicting with other trait rewards, by using Scumbumbo's XML Injector.
https://scumbumbomods.com/xml-injector/

It's also easily doable by combining the XML file yourself without using a third party software, that being said, mod the sims requires that you list which mods you conflict with, and these mods do conflict.

More options are always better. Thank you!

Thank you for this mod, it's much appreciated.

Could you please explain how a modding ignorant like me would be able to do this?

I want to thank you for this, but I also want to let you know that you have an error in the "Zeldagirl180_Titanium_Bladder_Trait_Titanium_Bladder" file. The line that should have TODDLER in it has some unused tag, so your mod won't work with toddlers. Wanted you to be aware in case that was not intentional.

I also suggest using the XML injector to dynamically modify the rewards store rather than overwrite it, this way your mode won't potentially break or cause issues with other mods.

EDIT: I misread your post thinking you said they DON'T conflict. Ignore this.