Zach, you're right man, let's keep it positive. Still don't know squat about what you like to paddle, but the truth is (and why this thread seems so fake to me) is that there's no summertime ww boating in Sonoma.
You'll be able to scrape down the Squaw Rock section of the Russian at these flows for a few more weeks, but scraping is an understatement, not sure if you like sliding over willowy, bone-zone, blast rock. There are miles of slightly swift and then flatwater on the Russian starting below the ww section and going all the way to the beach. The lower Russian is quite the social scene in the summer, but you might already know about this?
The East fork of the Russian in mendo county near Ukiah runs with diverted Eel river water later in the summer through fall and is a fun class II with a portage/V. But this is a two hour drive from Santa Rosa and I'm not sure what side of town you live on.
It would be almost entirely unlikely, but convective thunderstorms are happening more regularly in the N. Bay, in which case you might find summer water in the Santa Rosa playspot under the bridge at these coordinates: 38°26'18.4"N 122°44'34.9"W Ditto for Mark West Creek, which like much in our state got overgrown by foliage during the drought.
Your best bet for active summer paddling is the coast. Dillon Beach is a super friendly spot for boat surfing with plenty of room and the rock gardens to the north of the beach are fun to bash through, especially now with flat conditions. Also check out Goat Rock near the russian river mouth and head north or south for more awesome rock gardens. Here's a great link for real-time swell conditions: http://cdip.ucsd.edu/recent/model_images/sf.png
Blue is a great color for venturing into rock gardens. Bolinas is only 45 minutes from Petaluma and is a good summer spot for yaks.
People also like to overnight at estero americana, launching at the hwy 1 bridge and paddling the flat-water estuary 12 miles to a secluded beach between bodega and dillon.
Your best bet is to travel. Right now there's snowmelt in the sierra and after that's done the closest runs are on Cache Creek, which is east of St. Helena and the Pope Valley and further on to the S. Fork American standards, Toulumne, Feather, Trinity and all the other dam release runs. Maybe you already know all this stuff? Not sure...
Map of CA runs: California Creeks - Map of Rivers
Russian: California Creeks - Russian River above Asti
Cache Creek California Creeks - Cache Creek
Mark West California Creeks - Mark West Creek
East Fork Russian California Creeks - Russian River East Fork
Chili Bar and the Gorge California Creeks - South Fork American
It'd be great if someone else could provide links to local paddling shops, outfitters, vape shops, beer gardens, or maybe a link to their favorite boat for summertime whitewater boating in Sonoma county.