Do you want to increase tax revenue, or tax rates? The two are not necessarily the same, depending on which side of the Laffer Curve we currently occupy.
Tax revenue as a percentage of GDP is now, and has been for a decade, lower than it was in the 50's and 60's. Since the 50's and 60's were the two decades when we rose to superpower -- with the highest sustained GDP growth in our history -- empirical data says we are safe to at least go up to that level.
I would posit that we are almost certainly in the big hairy middle section of the Neo-Laffer Curve. That is, even without the evidence we gathered during our golden era, I would still suspect we are far from the point where excessive taxation becomes a primary cause of reduced GDP growth.
a revenue reduction concurrent with an even larger spending reduction.
Yes, as soon as we get that big spending reduction (which I favor), we can take revenue increases off the table. Meanwhile, I remain a fiscal conservative; our deficit is excessive, and we must do all of: cut defense, cut health spending, cut social security, and increase revenue until we bring the deficit under control. We cannot tolerate saying, "But not the one I don't like." Bullshit. Cut them all, and increase revenue, until we get the deficit under control. Then we can have our pudding, but we can't have any pudding if we don't eat our meat.