Hi,
I've just replaced an "In House" SEO with a consultancy model. The process related to me from the in-house guy was very bureaucratic as you have said.
From a consultant perspective I need to prove what I do does have a difference to te bottom line and then this builds trust.
Work out what will make a difference to the bottom line and attack that first. In my situation, they'd been running AdWords unsuccessfully for a while so I managed to get a small budget (£100) to prove a point. We ran a campaign for 2 weeks and got a noticeable spike in traffic and business. This has built the trust in my approach and process enormously.
On the reporting side I only report once a month in writing with other ad-hoc verbal reports of how things are going. Slipping in one or two suggestions about direction and budget in the verbal reports can be very beneficial.
Report less - Do more.
When reporting try to focus on the "what you did, what outcome you expected and what you learned" This should then feed back into an SEO Plan and overall strategy. In terms of SEO I've found business leaders like strategy.
Hope that helps
Steve