Never used eSata here either... IMO it wasn't very well thought out due to lacking power. These days it's somewhat redundant given that USB 3 is on most computers.
Can't say I've experienced the problem of slow USB 3 on drives although the cheap 2.5" cases I bought might have that problem, would have to investigate further as I found when I put an SSD on it the performance was pretty piss-poor.
Never bothered with optical audio out. In fact my soundbar has digital via coax hooked up and I just used a cheaparsed RCA cable and that works fine. Given the low bitrate required for even 5.1 audio I don't see the point, really it's just another big audiophile exercise in gross wankery.
My Windows equipped 7" tablet... even though by PC standards it's pretty paltry, I've barely ever used it although it's versatility is unmatched. It's got HDMI out so can hook up to a TV or bigger monitor and I've got a powered hub that allows using tablets while charging them with other devices plugged in.
Bluray - OK, it's like 10 years old or whatever. But I've had my Bluray player nearly 5 years and probably played 4 or 5 actual BR discs in it. Though it gets used practically daily for media playback over Wifi. Very occasional DVD use (usually data one), occasional playback via USB. My DVD player, don't know why it's plugged in, don't think I've used it since late 2012.