@lucasPeni
No. As long as your wireless network provides a good consistent signal that your Roku (or other devices) can connect, replacing with a wired device won't make a difference.
You only need around 25 Mbps to stream. Heck, I've successfully streamed with ¼ of that speed (not 4K). Gigabit Internet won't make a difference when it comes to streaming.
You could add a network adapter to your Express 4K+ if you want, but it really won't improve things. You seem to have a good setup as is.
Now, if you have a spare TV, and you want to move the Express 4K+ to it and replace with an Ultra on your current, that would be an excuse to buy a new device (of course, "because I want to" is always valid; I use that a lot). But unless the other features of the Ultra are worthwhile to you, there's no reason to replace what you have. Other than "want to."
DBDukes
Roku Community Streaming Expert
Note: I am not a Roku employee.
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