You lack imagination. If China is fighting the US, it is fighting the US in the whole world and US will also use all its bases in the whole world on this fight. Which means US bases in Diego Garcia to the Middle-East to Europe, any of them can launch Bombers and Missiles against China. And China will also not let those bases intact either. It needs to destroy them to prevent not only US ability to airlift supplies but also prevent those long distance tanker supported attacks.
And for H20, the entire CONUS should be its target. Entire US ability to wage war including air bases, training centers to factories should be targets for H20.
So, No, there is no lack of targets and 100 Bombers are an awefully low number. And I haven't even brought all the allies of US yet, if they support US military, they are also legitimate targets.
My point is that the economics rapidly disadvantages bombers because airborne refuelling requirements grow exponentially past a certain point.
My guesstimate is that for targets beyond the 3IC, the cost-capability equation highly favours aircraft carrier strike groups over bombers. So the bulk of spending and capability should go towards the Navy for these target sets.
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Also note that I've previously written (many times) that China should build a blue water Navy significantly larger than the US Navy.
This will be able to control the high seas and protect China's global trade.
But if required, such a Navy would also allow China to isolate the US with a blockade and also attack targets in CONUS.