No, no, no, no, no, no, no!
NEVER attempt to justify another ukulele (especially a tenor). That leads to the illogical, yet irreparably damaging, notion that a ukulele needs to be justified. It simply is. Once you start questioning why another one is acceptable in your (or anyone else's) life, you will start to question everything else around you. Laws. Politicians. The gods. Social order. Evolution. The superiority of cats. The banality of Anne Coulter.
It's a downhill slide from there. Pretty soon you're at the bottom of the philosophical heap, unable to come up with a compelling reason to buy that extra uke and waste your money on petty necessities like food, rent and the new Richard Dawkins' book. Or maybe the latest collection of remasterd Beatles' CDs (both are, of course, necessities).
Don't go there. You have been warned.
Take my advice: get a new uke every time an old one starts to sound like its strings need changing. That way you transmute dull into bright, like a musical alchemist. Never, ever, change strings. Sell the uke instead. But always replace it first with a new one. And never, ever attempt to justify another one.