The West Ridge is supposedly class 3, but it looks quite convoluted. It doesn't really head in the direction of Whitney anyways. The rest of the west face routes are class 5. Some of the best crack climbing in the Sierra can be found there, but these aren't the descent routes you're looking for.
The easiest route on Russell in my opinion is the South Face, Right. It's one short (40 foot?) fairly steep section of class 3 and a whole bunch of easier scrambling and talus/scree hopping. Finding the route isn't necessarily easy from above. If you are not able to locate it, the alternatives are class 4 or 5 and you'll probably want to rappell (one 50m rope should be enough).
The East Ridge is quite long, never all that hard, but exposed in some places. It's a great route, but to retrace it before continuing to Whitney will take more time.
If it were me, I'd go up the East Ridge and down the South Face. Then, depending on the amount of snow/ice, I'd either climb up the north slope to meet up with the upper part of the Mountaineer's Route, or else I'd follow the beaten path over the Russell-Whitney Col and traverse over to Iceberg Lake and the start of the Mountaineer's Route.
But it's not me; it's you. Good luck with whatever you decide and stay safe.