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Hey Indio,
There are a few things about eyepieces that you need to understand in order to make a sensible purchase. Eyepieces are more complicated than just their focal length. Focal length is only the start of a very long story.
First, wide field. This is very involved. You may have noticed that there is a thing called Apparent Field Of View (AFOV), and that it is described as an angular value, such as 52deg, 68deg, 83deg, etc. It describes the apparent angular width of the field that is visible through the eyepiece.
Now, there is a catch. For a given AFOV value, there is a maximum focal length that will allow for this value for a given barrel size. Barrel size is the 0.96", 1.25" or 2" eyepiece barrels typically used with telescopes, with the latter two being most common. Best way to describe how significant this is, is with an example. Take two straws, both the same length, but one is wider in diameter than the other. When you look through each straw, you will notice that the larger one will show a wider true field than the smaller one. Now, say you put an eyepiece into each straw, no matter how long you make the focal length of the eyepiece, the smaller diameter straw will never show as much of a true field as the wider straw. This is the same with telescope eyepiece.
When you look at a line of eyepieces within a specific AFOV, you will notice a few things. We'll take as an example the 68deg AFOV. You will notice that in the 1.25" barrel size, the longest focal length you will find in this barrel size is 24mm. You just cannot get a 1.25" barrel eyepiece with a longer focal length than 24mm that gives a 68deg AFOV. The 1.25" barrel just won't show more of the sky.Yes, you can get a 40mm 1.25" eyepiece, but it won't show you any more of the sky than a 24mm 68deg eyepiece. You will only get a smaller, much smaller, AFOV, closer to 35deg actually. Now, if we use a 2" barrel eyepiece, the longest focal length that will give a 68deg AFOV is 42mm.
If we stick with 1.25" eyepieces, there is a maximum focal length for a given AFOV. 52deg AFOV, the max fl is 32mm. 68deg is 24mm. 83deg is 17mm. 100deg is 13mm. While all these numbers may seem totally unrelated, what all these eyepiece values have in common is that they all show exactly the same maximum amount of they sky. That's it. The 1.25" barrel just won't allow more of the sky to be seen.
And conversely, there is a maximum focal length to AFOV relationship with 2" barrel size.
There are other elements that make for a better choice in eyepiece for your scope, but to note these down now would make for a ridiculously long post. I think you have enough to consider here now! If you would like more info, just ask. Eyepieces are a very vexed proposition that is shrouded in a lot of misunderstanding.
Mental.
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