Yes, of course those are great options too. They are another aproach to the middle position, which is neither better nor worse.
I like to have my middle be different. Really have a throwback in there, like having the same voicing idea, but a different aproach to it. Something I can use a lot when playing clean as a different flavour then the neck, which as a HB has a whole nother character. I also like the dirty vintage feel when using gain, without dropping too much volume (canīt underestimate the output of the IT and SH, even though they are lower then the SN and TS). A slight volume drop is something I use as a tool sometimes, as I will switch from bridge to middle when playing full instead of powerchords. Also I feel that most of the time a vintage hot SC will sitt better with split HBs.
When you go trilogy or sinner, you stay more in line with the HBs I guess, which can be exactly what you want. The volume drop and change in voicing will not be as apperant, though at least the sound difference will still be very noticable, which after all is a good thing.
When searching a middle for say a nailbomb or painkiller, the choice would be easier, as the trilogy and sinner would certainly win, but with the HD and Emerald, I feel that both are viable options.
I personally, for what I use the middle for would go IT.