It is said that once you have looked through a Nagler, nothing else will be good enough for you. As a Nagler owner, I think they might have a point. Sparked by the success of the TeleVue eyepieces, the Japanese have gotten into the act. The Meade Super Wides and Ultra Wides are virtual clones of the TeleVues. Vixen's Lanthanums and TeleVue's Radians throw out a generous 20 mm of eye relief regardless of focal length, and are a godsend to those who must wear glasses while observing.
Many observers find a barlow lens to be a valuable accessory.
Inserted between the focuser and your eyepiece, a barlow will typically double or triple the magnification of any eyepiece. Thus, for, you have effectively doubled the size of your eyepiece collection. Also, a barlow preserves the eye relief of your longer focal length eyepieces, thus reducing the amount of squinting you have to do. This is a tougher question to answer than you may think. What you can see depends on a lot of factors, including the type of telescope you bought, the quality of your local seeing conditions, and your level of skill.