I'm a massive Born of Osiris fan, and I'd have to say that I think everything you suggested is definitely a step in the right direction.
Especially using better key sounds, this lets them down massively.
They could really do with a few more repeats of particularly good parts. There are always bits in their songs that I think sound fucking incredible, that they only ever play once, and not for particularly long. Their songs are almost always so short too, that they could quite easily get away with making them a fair bit longer.
More mechanical stopping and starting! I guess I really just mean guitar editing. The New Reign was edited in a very robotic way, which I guess might not be to some people's taste, but I feel like it really added something to the sound that A Higher Place was completely missing. Without it, it sort of takes the progressive edge away from them and makes them sound more like every other Deathcore band.
More irregular time signatures. Especially on the drum fills (like the beginning of Brace Legs). I guess that might not be something you can really change, but meh.
Less songs that start off sounding like Chimaira.
To be honest it's fairly obvious that you know what you're doing, I'm sure it'll end up sounding awesome.
Already looking forward to it!
