I feel like the problem here is that people have different perceptions and ideas of what they feel like shounen is. I've honestly seen this kind of debate happen quite a lot, it can be a difficult thing to define properly for a lot of people and everyone draws the line at different places. The way I think of shounen is not the same as the way you think of shounen, and so an RP made to reflect the way I see shounen may not fit with the way you see it. I've listened to everyone's complaints and have been trying to be reasonable and alter my rules, but I feel like what some people here seem to be asking for is a complete upheaval of the RP, which is just simply not going to happen. If what I've already changed isn't enough, then maybe this RP simply isn't for you
For what it's worth, I do intend for the characters to learn more powerful attacks and get stronger as the RP goes on
Where does the OP say that it's all those shows in one? The OP actually lays out My Hero Academia, Soul Eater and Naruto as the biggest influences, and I know at least Naruto out of those three keeps thing constrained to chakra. Sure, chakra can do a lot of stuff, but you're not going to see somebody fighting in a mech suit in Naruto.
In all fairness, Naruto did kinda get a little ridiculous around the Shippuden era (though I guess that's also the part of the show where most people seem to agree that it went downhill for that reason, me included)