It's not really a matter of complicated or not complicated. It's a matter of what the tax system does. Maybe a less complicated code would work better - but not simply because of less complexity, it depends what actual changes you make.
Either way none of that is at stake in this election. Right now the problem you've got is this. Assume you think the national debt is a priority and should be reduced as quickly as practically possible to something like, say, 5 trillion instead of 16+ where it currently is.
Every year you have a budget deficit of 1 trillion dollars, give or take. So, you need to engage in spending cuts and revenue enhancements that, in combination, add up to 1 trillion dollars.
First of all, Obama won't do this. If re-elected, it's not unlikely that the annual deficit will end up looking more or less the same for the next 4 years and he'll leave office with 20 trillion in national debt.
However, Romney won't do this either - or if he will, no one has any Earthly idea how. He intends to increase defense spending by a significant amount, and reduce tax rates in a number of areas. In other words, increase spending and reduce revenue. On its face, this would suggest that his policies will result in an even HIGHER annual deficit than currently exists and an even HIGHER debt in 4 years than 20 trillion. This shouldn't really surprise anyone because significant increases to the national debt have been the result of every republican administration for the past 30 years.
But Romney says he wants this all to be more or less revenue neutral. How? Well, by eliminating certain spending and eliminating certain exemptions and deductions. But which ones? He refuses to tell anyone. So far, we know of two things. First, he will end subsidies to PBS. Whether or not you think PBS is a good thing to cut, that is at best about $400 million annually. Cool, but we're looking for 1 trillion here, man. 400 million isn't even a drop in the bucket.
The second thing we know is that he will repeal Obamacare (the ACA). So that should save some money, right? Well, actually, no. The CBO reviewed the actual budget impact of legislation repealing Obamacare and calculated that it would actually add 109 billion to the deficit over 10 years. So this is actually going in the OPPOSITE direction of where Romney needs to go. It makes the deficit WORSE.
This is the problem. If the Romney campaign could come up with a list of bullet points that would a) generate more revenue (besides "we're going to improve the economy because we say so so everyone will make more money and the government will tax it" wishful thinking), and b) reduce spending, that would be great. They need to add up to at least $700 billion from where we are now - at least that puts you in striking distance of a balanced budget.
Here's the thing though. Imagine he did it and balanced that budget, found all $1 trillion dollars - great success. Except the debt is still 16 trillion. You not only have to find that trillion bucks of net revenue, you then have to find 16 trillion more somewhere - probably over a number of years. I.e. even if you're in a $500 billion surplus position, and you use every penny of that surplus to pay down the national debt, it would take you more than 3 decades to get rid of it.
So on fiscal issues you're fucked no matter who you vote for, is kind of what I'm saying.