Apparently Russia has their strategic bombers on high alert. Looks when phase 2 start Russia is going to go all out on the Ukrainian armed force
I'll believe it when I see it.
They are targeting critical infrastructure all over Ukraine. Remember something important: we're not really seeing the full picture of everything the Russians are taking out because the Ukrainian government has made it illegal to publicize such information. For all we know, the Russians have already knocked out many of the targets you're talking about. Why would they disconnect the nuclear power plant? Has it occurred to you that it might also control the power supply for Russian-occupied areas in the south? I don't think the Russians are holding back as much as you believe. One area where I might agree: air power. I definitely think the Russians have much more they can throw at the Ukrainians from the air. We'll see now if they finally take all the gloves off.
They're targeting a few oil depots and a few military targets. The amount of ordinance fired at this point matches what NATO would do in 1-2 days. They haven't targeted the roads or infrastructure that Ukraine is using to resupply even though it would lead to the end of the war pretty quickly for them.
The Russian millitary campaign so far just seems like a poor impression of a NATO one.
Cutting off power makes total sense. No power and Ukraine would be forced to use diesel generators, less fuel for tanks. Or import energy from the west (which again you could cut off by bombing infrastructure). None of this has been done by Russia, which tells me it isn't taking this fight seriously.