Just finished what's done so far of this hack, here's my thoughts on it.
Starting with the gameplay changes from the original game...I have some issues. First off, the map size. Now, I understand it would be immensely hard to put FE4's gigantic maps into a hack of FE7. But, splitting the chapters like this is irksome to me, mostly for story reasons. The giant maps in the original, at least in my opinion, help world build, (Geography for example) and give the conflicts and battles more scale and depth. In some other cases, splitting them feels sort of awkward; like in the Prologue, fighting Dimaggio and Gerrard, then Gandolf in the next chapter takes some umph out of the fight. To sumerize, I understand why it had to be done, but I'm iffy nonetheless.
As for a collective gold supply...it feels weird when applied. 4 is built around choosing who to fight who so they will get the item drop or gold, to the point where theives actually have a purpose other then looting. Making it collective takes that whole layer out. To a lesser extent, this applies to the edition of trading as well. To add a nitpick, the removal of gradual village destruction is annoying. And for a really minor thing, I miss the whole castle guard mechanic.
There's also the portraits, which I find a mixed bag. Some are great like Alec and Noish, and some just flat out don't work, like Aideen and Kurth. The main issue I have with them is the shading and modelling is all over the place. Some portraits are done in the style of the typical GBA mugs, then others are done in this weird muted gold. A few even clip through, such as Byron. All of them share the distinction of being full body shots, which sometimes clashes with backgrounds.
The actual hacking itself is done pretty dang well on the technical side. Kudos to the remixes and custom sprites in particular.
Overall, I give this hack a 7/10.