the thing that makes the odd time signatures more challenging is the fact that they are not as familiar. most of us don't have to even think about playing in 4/4; we've been conditioned to it for years and years so it feels completely natural. one of the things i like to do is write grooves that fit odd time signatures that are easy to internalize and play without intentionally counting. by becoming accustomed to playing these grooves, the cycle of the odd time pulse begins to feel more natural and over time after playing more and more of these grooves we sense the cycle of each measure without stumbling.
now, when it comes to soloing, it also helps tremendously if you can 'sing' or hear these grooves in your head underneath what you are playing. it gives you something solid to hold onto and reference even if you are not playing that exact groove. a lot of drummers use a similar approach when soloing in jazz so that they do not get lost in the form. they will basically sing the melody of the tune in their head while they are soloing so that they stay aligned with the form. it's like doing 2 things at once but it's actually easier than you might think. the other benefit is that your soloing phrasing will be likewise influenced by the groove or melody that you are singing in your head, so that you incorporate an interactive element into your phrasing.
anyways, these are just a couple of concepts out of many, but i hope they help you out-
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