So those tires are getting near the end. No done yet, but getting there...
The issue with tread area cracking is will they let water into the belts? If they do, they can come apart pretty easily. If they stay dry - no biggee. I've had terrible luck with Michelin's cracking before they wore out. Once it starts, they are getting iffy. So no more Michelin's for me.
Toyo and Yokahama have been real good about not ozone or UV cracking. I've recently gone pretty much all Kenda as they worked great on desert bikes and ATV's w/o cracking, so they were on my Saab (sold), and are now on my F-150. Just could not justify the cost of the two brands I know are long lived.
Bridgestone are somewhere in the middle between Toyo and Michelin ... Goodyear are good with truck tires, but their SUV stuff just does not hold up to rocks at all. Big O used to be the way to go if off-roading in the desert because they were replaced w/o question when they got cut. But no more...
So you have to buy your tires based on use criteria. For motor homes that sit and sit, you need Toyo or equal. Otherwise you be buying tires while yours look good, but blow going down the highway. For trucks, it's a bit different depending on Ply rating ...
Cars, vans, and SUV's need what matches their annual mileage, road type (paved, gravel, dirt, etc.) and weather expected. If you have real winters, you have another issue to deal with ...
Me, I'd run those tires down some more. But, I'd carry a can of Slime in the trunk and decent tire pressure gauge. I'd be checking them at least weekly. IL will throw weather at you, and any water in the belt zone with a freezing night might be the end of a tire ...