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Depends what you want to use your low power eyepiece for. If it is for viewing DSO's with maximum contrast and a good wide field then yes, get an eyepiece that will give you a smaller exit pupil. Both 27mm and 24mm Panoptics are excellent choices. Dont worry about the 0.4mm extra on the 27mm over your ideal 5mm exit pupil for your eye.
If you want to get maximum field of view for general scanning and star hopping then a 41mm Panoptic will give you that with a nice 2 degree field but with an 8.2mm exit pupil. Since you are only looking at field stars the larger exit pupil will be of no concern. The Pan is of course expensive and a 55mm Plossl will give you the same true field but with an even greater exit pupil which again is not a problem when star hopping. The sky will however be quite grey with the 55mm Plossl.
Now after saying all of that a little bit of contrast and magnification is preferable so the 41mm Pan is a better choice over the 55mm Plossl since you get a bit more magnification to help spot some elusive DSO's and better contrast. The 35mm Pan would also be a good choice and will give you about 1.7 degrees TFOV.
Now if you have a good finder you don't need a wide low power scanning eyepiece so go with either the 24mm or 27mm Pan. If you dont have a good finder or prefer the Telrad, go the 41mm Pan since its field is equal to the middle circle of the Telrad (2 deg).
As an alternative to the 24 or 27 pan, consider the 20mm Nagler which will give you a nice 4mm exit pupil and the field of the 24mm Pan (1.2deg). Perhaps at a later date you can complement the 20mm T5 with a 31mm T5 for your low power scanning eyepiece.
Whatever you choose, enjoy!
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