For a roof this small I don't think it will be a critical difference if it is 1" vs. 1/2" pitch over 4'. What matters is that all of your flashing details are done right, both at the house and at the drip edge. The only person that will ever notice this is you, so don't get too hung up about it. You also want to make sure that this little roof is vented in every bay as much as possible. If not, they almost always start rotting and peeling paint off everything within a couple years. If you have any hollow wooden columns, these should be vented top and bottom too.