Epic filtering on Strategy Roadmaps

It would be really useful to be able to filter at the Epic level on the strategic roadmap. The current filters (i.e. release settings > show parking lot) only apply to the initiatives. For example, we have cases where items are in the parking lot (i.e. not yet planned for a specific release) but have been given initiatives for planning purposes. Because of this link, those unplanned items are shown on the roadmap without any way to hide them.

The strategic roadmap view is great but we are really struggling with this limitation. I'm sure we could probably create a custom roadmap as a workaround but they aren't as user-friendly or accessible as the default strategic roadmap.