I think it's insightful because it keeps the enemies as a constant variable so it shows you how different each character's approach to handling those fights are. I would like additional battles that are individually tailored to each characters' strengths and weaknesses too. Need moar DLC.
I would have liked that the challenges of the coliseum and the battle simulator had been treated in a more original and interesting way, instead of proposing copy and paste challenges for 80% of the challenges offered.
Because this is, basically, the level of superficiality with which these challenges are proposed:
Challenge 1 Cloud (easy): defeat enemies A, B, C, D alone.
Challenge 1 Aerith (easy): defeat enemies A, B, C, D alone.
Challenge 1 Tifa (easy): defeat enemies A, B, C, D alone.
Challenge 1 Barret (easy): defeat enemies A, B, C, D alone.
Challenge 2 Cloud (normal): defeat enemies E, F, G, H alone.
Challenge 2 Aerith (normal): defeat enemies E, F, G, H alone.
Challenge 2 Tifa (normal): defeat enemies E, F, G, H alone.
Challenge 2 Barret (normal): defeat enemies E, F, G, H alone.
Challenge 3 Cloud (Hard) : defeat enemies I, J, K, L alone.
Challenge 3 Aerith (Hard) : Defeat enemies I, J, K, L, alone.
Challenge 3 Tifa (Hard) : Defeat enemies I, J, K, L, alone.
Challenge 3 Barret (Hard) : defeat enemies I, J, K, L alone.
[and this process has been applied both to the challenges of the coliseum and to the battle simulator]
(because 80% are like this)
And even if yes their approach may be slightly different because you use a different character, the juice does not change.
Because you just have to keep the same set of Materia and the fear passes.
For this reason I found them made, generally, in a very superficial way and without any commitment from the developers.
(with rare exceptions of 2 of the challenges for 3, at the Shinra battle simulator n°2, Hard mode)