Eyepiece recommendation for Orion XT8
This is all subjective. Ask three different people about eyepieces and you'll get three different opinions. My answer is not the right answer, it's just my view as an amateur who has a case full of eyepieces.

The main difference between the less expensive and the more expensive eyepieces is in the quality of the view towards the edges.
Almost all eyepieces will give good views in the centre of the view. It's towards the edges that the view starts to degrade.
Wide field eyepieces need more lenses to provide a well-corrected view to your eye. But the more glass you add, the more surfaces you have which can reflect light back and away from your eyes, so this glass needs to be well-polished.
This is why the expensive eyepieces cost as much as they do. To provide a wide field that's well corrected at the edges needs lots of quality glass, and a good QA process.
Finally, there are definitely diminishing returns when paying more money. The difference between a €50 eyepiece and a €200 eyepiece will be more apparent than the difference between a €500 and a €1000 eyepiece.

I see three main groups of eyepieces:

€1 to €199
€200 to €399
€400+


The first group consists of a lot of different brand names all selling pretty much the same eyepieces.
Generally speaking, a factory in China makes a batch of eyepieces, and different brands buy these eyepieces and pay the manufacturer to put their brand names on the eyepieces they buy.
The brands who pay more money probably get to pick the better eyepieces from a production run.
Or take the case of Explore Scientific, who are partnered with Jinghua Optical Corporation (JOC), which suggests a closer relationship and explains why some of Explore Scientific's eyepieces (the 92°, 120°, and 3&quot; 100°) aren't available under other names.
The eyepieces in this group are mostly all much of a muchness, but there are some gems to be found (the 8.8mm 82° offered by ES and Meade, or the Orion E-series 7-21mm zoom).
Also, it's perfectly possible to buy a €50 eyepiece and get lucky with a great manufacturing sample that gives eyepieces ten times its price a run for their money.

The middle group begins where I see a noticeable increase in optical quality.
The Baader Morpheus 76° eyepieces are at the lower end, and are an example of some fine &quot;forever eyepieces&quot;, as you put it, which won't break the bank. (They're slightly more expensive in the USA than Europe, I believe, which might make the Pentax XW a better option if you're in the Americas)
APM have some good eyepieces in this price range, too, such as their 100° series (which many experienced observers have said are the second-best 100° eyepieces available today) and their 12.5mm 84° eyepiece.
Pentax's 70° XW range are well-regarded, with eyepieces from 3.5mm to 40mm.
Also Tele Vue have their &quot;budget&quot; Delite 62° eyepieces in this price range.

The expensive group contains the Tele Vue Delos 72°, Nagler 82, and Ethos 100° ranges.
Right at the top are the Tele Vue Apollo 11mm and the Nikon NAV HW with 102° FoV, which comes in only two focal lengths - 12.5mm and 17mm - but comes with a screw-in lens to give an extra focal length, allowing for 10mm and 14mm.


So, having said all of that, what would I recommend?
Low power I would recommend the APM UFF 30mm. Other options are the Pentax XW, Explore Scientific, and Tele Vue Nagler. (You could go up to 40mm if your pupil dilates to 6.5mm in the dark).
By the way, at low magnifications a FoV of ~70° is wide enough, so don't feel that you have to go for an expensive ~80° eyepiece here.
Medium power I would recommend the Baader Morpheus 17.5mm. Another option is the APM Hi-FW 12.5mm. (I have both of these, and am therefore biased towards them, but they are my most-used and favourite eyepieces)
There are many different options in this range. Anything from 10mm to 20mm would be good.
You might even want to wait a while before buying a medium power eyepiece. Get the low power and high power ones and use them for a while, and you'll get a much better idea of what you'll want out of a medium power eyepiece.
High power I would recommend the Baader Morpheus 6.5mm. Other options are the APM 100° 7mm, the Pentax XW 7mm, the aforementioned Meade/ES 8.8mm.
There are quite a few different options in this range, too.
(At high magnifications the main thing you'll want to consider is minimising &quot;time to nudge&quot;: when observing a planet you want to be able to have it drift across the field of view for as long as possible before you have to nudge your telescope to bring it back into view.
For this you'll need a high FoV eyepiece - 82° is a comfortable minimum these days, now such a relatively high FoV is widely available at reasonable prices.)

This answer has become a lot longer than I thought it would. And I haven't even mentioned zoom eyepieces yet! (You could get a zoom. And a Barlow. And a low power eyepiece.)
Another option is to buy a set of SVBONY eyepieces and use them for a while, and gradually replace your most-used focal lengths with better quality versions.
But I'll wrap up. To conclude: don't take my word for it! Get some more points of view. Read some reviews. Spend some time with the astronomy.tools FoV calculator to plan the focal lengths you want to have in your eyepiece collection.
(And if you decide to go for the expensive eyepieces then look at the second hand market - people generally take good care of their expensive eyepieces, and some brands maintain good resale value)