I concur with Abdul and Tapirus, that substantial gains Russian colonies would likely depend on an early point of divergence, be it gold-up or Tsar-down. This has been something I've often wondered about, but I must admit my own interests stray more to something later. Being curious how it would play out in recognizable circumstances, that limits things to Fort Ross.
I've already gone on about the troubles of Fort Ross, which by and large was the perfect 17th century colony, with the misfortune to be set up in the 19th.
Now, just up the coast is the Willamette Valley, containing some of the world's best cool-weather farmland. Had an early Russian explorer found the place, that would have been the obvious spot to build, even for the agricultural illiterates involved. It wouldn't be easy to find, IIRC, due to the passage of the Columbia River mouth, but it's possible.
They were trying to build in a location where they would also have access to sea otter, which does make a Portland settlement a problem. However, it's one easily solved. We take as point of divergence a wealthy Russian adventurer Mikhail Ulyanov. Fleeing scandal and possible litigation in Moscow, he hurriedly liquidates his assets to finance an expedition to the New World. Ulyanov arrives in Alaska in 1809 just as the first expedition to California returns from scouting out Bodega Bay laden with sea otter pelts. He manages to cut a deal with local officials to use their facilities in exchange for a cut.
He sails down the coast in the one rather ramshackle ship he could afford. A near fatal storm off Washington forces him to put in near the mouth of the Columbia to make repairs. In the two months these take, the crew purges the local beaver and sea otter population while their fearless leader explores the interior. When he finds the Willamette, he sees a gold mine.
This is a Russian nobleman we're dealing with, not the sort of hunter-trapper-sailor that composes his crew. He's actually put in hard work on a farm (albeit beating his peasants for disrespect). It doesn't mean he could grow more than a beard unaided, but he can recognize good soil. Ripe with fantasies of an estate beyond any potential prosecution, Ulyanov briefly returns to Sitka, only to sail out once more. The following two years is spent working up seed money. He leap-frogs along the coast, collecting pelts around such convenient berths as he can find.
In 1811, OTL's Kuskov expedition to Bodega Bay by the Russian-American Company ends in failure as in OTL. Knowing another is planned for the following year, Ulyanov attempts to nominate himself as the leader of a colony at his alternate location. His efforts are to no avail. With the excuse of a fur shipment to the Russian Far East, Young Mikhail scours Asia's Pacific Coast for experienced farmers with little enough backbone to make a good peasant. Being on the wrong side of Siberia, he settles for experience. With a dozen men and some draft animals in tow, he heads back to Alaska, intent on founding his colony.
He is disappointed.
In our timeline 1812 saw Kuskov's second attempt to settle Bodega Bay, which had been judged an excellent prospective site. This was partially a matter of the natural harbor (vanishingly rare on the Californian coast), but primarily the result of an especially abundant sea otter population identified in the 1809 expedition. On arrival three years later, the Russians managed to be surprised at the scarcity of the animals, despite having taken the time to empty the Bay of them on their previous visit. As it happened, sea otters were just one of those species - too profitable to harvest, too slow-breeding to survive the process. By 1817, in fact, the combination of American, British, Russian, and Spanish efforts had so thoroughly depleted sea otter populations that shipping costs could no longer justify intensive harvesting. This was one of the major reasons for the stagnation and disappearance of Fort Ross in OTL, as it had used otter pelts as a crutch to support its weak agricultural production. Ironically, this may actually have saved the Californian sea otter, as remnant populations stabilized where larger populations to the north eventually went extinct.
So. In this TL, Kuskov still finds Bodega Bay otterless, and still sails north to OTL's Fort Ross. In this TL, however, Fort Ross was one of the locations Mikhail Ulyanov used, and is similarly depleted. Given that it's only advantage over Bodega Bay was its otter population, Fort Ross is disqualified. A brief debate ensues on whether to continue north to what appeared to be a marginal site in our Oregon or return to Bodega Bay, with the former eventually winning out. The third site looked good from the sea, but manages to be a colder Fort Ross and - looking just as good to the Ulyanov Expedition - has fewer otters than hoped for.
With growing discontent about the repeated changes, Kuskov redirects the expedition to near the site of our TL's Portland, coopting the site recommended by Ulyanov. An initial landing base at OTL's Astoria is fortified and then abandoned for want of men to defend two such distant positions. Defense is a real concern here. Portland is too far up too violent a river to be easily relieved by sea and the native populations remain relatively large. As such, when Ulyanov arrives in 1813 with a new batch of armed settlers he and his little cadre of "experts" are given a hefty stake in the colony, much to the disgust of Kuskov's bunch.