Simplified approach for improving Processes
start with the processes closest to the flow of money through the business.
Not because other processes are unimportant, but because improving a revenue-generating process creates more capacity, more cash, or both. That then gives the business the means to improve everything else.
I'd probably order them like this:
Delivery - from customer commitment to outcome
Finance - from cash to insight
Sales - from customer interest to revenue
Marketing - from generating customer attention to qualifing interest
Run The Business Rhythm - from planning, to setting priorities, to review
Map each process visually (you will need the visual to spot the gaps and patterns and abberations)
Quantify the process - give it a quantiative measure - time is easy, so is money spent
Measure it as-is, without changing it, for a period of time. This step of measuring can be temporary, since measuring manually adds overhead. The period needs to work for the process itself and relate to how often it is done and how much time you might need to build a bank of data. If you are doing something daily, you may be able to meausre for a week; if doing something monthly, you may want to measure for a quarter or a half.
Improve it
Measure it again
Iteration is a friend in process improvement.