Much of this post "Slow Software" does not apply specifically to FileMaker, but personally, I like reading about other platforms and there are some valuable insights here. Also, this Hacker News thread about the post adds additional layers of insight.
"When discussing software performance, we often hear about throughput. E.g. "this web server can do 10,000 requests / second." But that's not how users perceive things. They care how long their particular web request takes, or how long a doc takes to open, or how responsive an app is to their clicks. These interactions are about latency. Latency is the critical metric we'll examine in this article."
How can we improve the user perception of how long tasks take (which may be separate from how long tasks actually take)?
"Most of the web does poorly. A ~1,000ms Google search result will feel faster than most of what you see online, though still noticeably delayed compared to a ~100ms interaction. And it's easy to find examples of pages that take ~5,000ms+ to load even on a good connection"
Does your navigation (FM Pro or WebDirect) load a record in 1 second or less?