I like the idea you brought up where if the evidence is found then you can show it to the suspect, or directly question them about it, and they would eventually speak out about the whole thing. It would honestly be a nice touch. I think L.A. Noire does this pretty well when you catch a lie, you can just bring up the evidence that you found and the suspect would give up and tell you everything.
I think if you want instructions to be slightly clearer, or have an easier introduction, then maybe a case where there are only three suspects (instead of seven) and you just leave the player to do the rest. Because kind of what I mentioned on my play through, I did felt a little overwhelmed with all the information and stories I got from interrogations. I had to constantly go back and review what I found on suspects' houses and see if anything fit with what one or the other said to me.
I think I said this already, but I do see this with a lot of potential and I hope you work on it some more.