Dataview needs to index files. Consider yourself lucky (for the low amount of files).
If there is a new (core) plugin made anywhere in the future, this time period could be incorporated in the startup time and have queried data be ready instantly.
As regards homepages with dataview queries (in my case numerous dataviewjs queries), I even don’t use those anymore but only manually open the canvas dashboard when I know all files are loaded. Otherwise (at least for my vault), sometimes I’ll even have trouble opening a normal md file… (There is some indexing interference that can break things for a while? Many times I got impatient and closed Obsidian and then learned to not have files open that instantly require Dataview. A longer story will be included in my memoirs.)