MrHorgy, before you write the 70% deal off consider that, so far, pretty much everybody who was offered 70% to join has been upgraded to 100% at the end of their first summer with the company. Similarly, people usually get to their base of choice after the same period. The rumour mill tells us that the company still has significant expansion planned and consequently as an experienced FO, you could expect a command pretty quickly, subject to training results.
Expect between 500 to 700 hours per year on the 737 fleet, depending on base. Things only really seem to kick off in late May/early June and goes quiet come the end of October.
Six on, two off is usual in summer, winter can be absolutely anything - I've even had three off, one on, three off!