Are there comparisons if is faster for beginners to learn to play on a isomorphic instrument?
On guitar in fourths tuning, you only need to learn each interval and chord shape once, compared to multiple permutations in standard tuning. Not sure how much difference this makes over the long run as another poster pointed out, but for me it made the process seem much less overwhelming and motivated me to start learning how to make my own chord voicings, which is something I wouldn't have done in standard tuning.
I tune in all fourths as well. For me it has made a huge difference since I made the jump some years ago. Putting voicings, patterns, etc., into muscular memory is faster and a lot less work. For my purposes, it makes the instrument more intuitive with a better ear-hand connection. Even very advanced players trip on the G-B strings oddity (with things like playing a fast, angular melody on different string sets, without preparation, for example).