Know-How Exchange : Other

Because each project and each client is unique, I would worry that a template-based proposal-preparation tool would not be very useful -- at least for the kind of strategic consulting I do. Further, I use the proposal process as a way of determining what my work plan would be, so I can quote a fair (and fixed) fee for the project. If there's a large creative component, I need to know that. If it's mostly mechanical, I need to know that. Etc.

Net, I would be leery of any template-based proposal-creation tool unless you provide pretty much the same deliverable all the time. (I also like to customize each proposal so it is highly targeted and directly relevant to the specific client for whom I am preparing it.)

Let's say you are putting together a proposal that requires listing several deliverables (for example a marketing plan, new website, and a social media curation program). Whilst the finer details of those deliverables will change case to case, there will be a lot of commonality as well. Rather than rewriting every module in full each time, when I was suggesting was a drag-and-drop type template where you could, for example, drop in the website development module and edit as needed.

If you've done these, why not just make your own from past work. Pull out the sections and put them into a document. Then, simply use or delete sections as required.
Or, do the above and then have a graphic artist and editor go through it all to add whatever logos, glamour and/or professional formatting touches as you desire. (Artists and writers don't command much money these days, so it won't cost near as much as you'd think.)
Of course, if you're trying to get into this without having done it...canned packages make all the sense in the world.