I don't know if it is worth repeating, since so many people obviously want to keep their "hero" and "villain" figures intact at all costs, but a lot of what they hate in Paul is probably not from Paul (e.g. the anti-feminist rhetorics of the Pastorals or the addition to 1 Corinthians 14, v. 33f), and what they love in the Gospels "Jesus" and oppose to Paul (e.g. freedom from the Law) probably echoes Pauline theology more than the teaching of some early 1st century rabbi in Palestine... to me it mostly shows that the narrative genre of the Gospels is infinitely more effective than the rhetorical genre of the epistles, which requires more intellectual effort.
Paul is first of all a thinker. And a fairly original one at that. You may disagree with what he thinks and dislike how he thinks, but you have to think along with him to be able to assess and criticise his thinking in a meaningful way. I would advise not to dwell too much on the "parenetic" or "practical" sections of his work (from which most "regulations" are drawn, and are actually the least characteristic part of his work when compared to comporaneous literature) and focus on the "doctrinal" parts (even if you are not particularly interested in religious doctrine). Romans 1--11 for instance. Paul's way of thinking is remarkably new and quite an event in the history of ideas, beyond religion proper, as a number of non-religious thinkers recognise (e.g. http://www.amazon.com/Saint-Paul-Foundation-Universalism-Cultural/dp/0804744718)