http://employmentsummary.abaquestionnaire.org/
Check out Madison's employment numbers from 2011. The website I would refer you to--lawschooltransparency.com--is being buggy for me right now, so I'll refer you to the ABA. For the class of 2011, 63% of Madison's graduates got full time jobs as lawyers. 10 of those people went into solo practice, which as a recent graduate is extremely volatile in terms of pay. 37 of those people are in firms of 2-10 attorneys, where chances are very high they are making under $50k a year. Taking that into consideration, there is a 44% chance of you having a favorable outcome from UW Madison. Would you bet $50,000 on a 44% chance of a favorable outcome? Would you be taking loans out for cost of living as well as tuition?
You should absolutely take the June LSAT and volunteer during your year off. It will do nothing but good things for your future. With a 4.0 and your natural test-taking ability, the sky is the limit. You could be looking at Harvard, Yale or Stanford (which give only need-based aid, so they may end up costing you less than you think), or a better school in your region with a huge scholarship. Don't limit yourself.
This is a compilation of admissions stats where you can see where people have gotten in in the past (and what money they've gotten) based on manipulating the numbers:
http://myLSN.info/t001g4
Note that no one (on the website this site pulls data from--lawschoolnumbers.com) with a 4.0 and a 170 has gone to UW-Madison.