You know those Trinkets that are common at low level -- Moog's Ornament, etc. -- that give +1 Enhancement bonus to a stat? Practically speaking, their only use is to let low-level characters raise a stat from an odd number to even. It's not long before characters have access to +2 Enhancement items or even higher.
However, if these Trinkets used a "Equipment" bonus or "Competence" bonus, or whatever seems appropriate, they would stack with the very common Enhancement bonuses. Even a mid-level character -- who has access to more powerful trinkets -- might like the option to make a stat even.
For instance, a 10th-level wizard whose Health belt gives him an odd Con could use Rahkat's Spangle, thus giving him 10 more hit points, like a False Life item. (Which it also stacks with, sort of.) Or he could use Zizoo's Spangle instead, and get 19 more spell points, which sort of stacks with Power items. Y'see.