Mixing Tires Sizes

[96C280]

Would keeping 2 215/60 15" tires on the back (1/2 life left) and putting 2 new OE 195/65 15" on the front have a detrimental effect in any way?

I'm eventually going back to the, hopefully, more compliant ride of the smaller tires on all 4 but wanted to know if I can use up the older tires before changing them also.

FYI, the 215s are nice if the road is smooth (and they fill out the rear wheel wells very nicely, a little bloated looking on the front wheels) but bot dots are their bane. Michelin Pilots XGT V4s. Going back to the MXV4's.