I think buying/supporting and holding longterm is the better option than renting hash, when it comes to making it more resilient.
That's a topic for discussion of course but i don't see a lot of sense in renting hash opposed to lifting the price in the longterm.
Renting is just 'you mining it'. Higher price is 'everyone mining it'.
My 2 cents.
That being said, Uno is still one of only a hand full of merge mined coins and has a higher hash than 98% of these other altcoins.
edit: don't be discouraged from renting hash though, it's also a good thing to do. Not sure my conclusions are 100% correct. You got to weigh the options yourself. Likely depends on how you look at it.