Well, your plan to drive to Oakhurst and then follow SR 49 will keep you below any chance of snow and should be trouble free. This will not really involve what we think of as "mountains," being more in the nature of foothills. I haven't been north of Oakhurst yet this year so cannot say for sure but you may find some wildflowers along the way. SR 49 can be scenic and is certainly in an historic area. The drive will take you right by the Wassama Roundhouse State Historic Park and the California Mines and Minerals Museum at Mariposa. Neither is particularly impressive but might make for an interesting quick stop.

There are some interesting galleries and photo/art studios in Coarsegold and Oakhurst and some places to eat.

If you are going to go as far as Oakhurst, I'd suggest just continuing on up highway 41 as far as you feel comfortable. After Oakhurst is the little mountain community of Fish Camp and beyond that is the entrance to Yosemite Park. If you get that far, just ask the ranger at the entrance station if you need chains and take his advice. If he says yes, just turn around and go down to Oakhurst for your turn onto SR 49. Again, unless you get stuck in snow or pass a snow check point, no police will ever stop you to see if you have chains. Even at a check point, the worst that might happen is they will tell you you cannot pass.