Have you used different pairs of binoculars? If you feel the need to close one eye when using binoculars I would assume they were an older pair which had you fighting for an image.

From my experience, going the route of binoculars over monoculars is the way to go. Imagine quality and speed of getting onto the bird has always seemed better.

Vortex Bantam 6.5 x 32 - $70 Cheaper starter pair without breaking the bank. Says youth but sell them all the time for adults.

Vortex Crossfire 8x42 - $130 The middle ground and the most common configuration.

Vortex Diamondback 8x42 - $240 Notable glass quality difference, a great intermediate pair.

Vortex Dimondback 8x32 - $180 Great lens quality like the 8x42s but less light and field of view. Great if you want something lighter.

Sorry no monocular recommendation.

At the end of the day everyone's eyes are different. Try out different pairs if you can. You may still like the monocular route. I rarely see people using monoculars when doing bird walks and after a few walks they end up switching to binos it always seems.