Hi James,
That looks like my approach. I add ERs with TrueVerb as inserts on several input busses (for dry instruments - horns solo, woodwinds (2x), trumps and bones and dry percussion). Then I have two reverb busses (front and back) which go to a separate PC, where I run PS with two True Stereo instances. In this case it is recommendable to lower the ERs in PS, because of the added ERs and the "wet" input channels that I also have (ProjectSAM groups). For the strings I use a different trick: I have one bus that adds some ERs to all the string sections. This subtly seems to blend them into the same space, after the narrowing and panning the string groups with Waves S1.
I really like the European Hall from the TC6000, with the "less ERs" option.
But I have a few different templates, for shorter tails I also like the Lex960 Large Hall, which strangely enough has its ER portion AFTER the start of the tail (!) - I noticed this when I switched the ERs off on the Lex. Anyway, it's a completely different reverb style, but very usable.
To be honest, I do not often check out other presets, but there are some very nice halls in both libraries.
It IS important to watch the amount of ERs when you add them like you and I do, otherwise the 50-150 msec range can become too muddy.
An interesting difference between the TC6000 and the Lex960 is that the latter is more based on psycho-acoustical research and less on "physical correctness". The ER range for instance is NOT how you would expect it from a real hall, but it does seem to give a better "experience" of space. See all the papers that Griesinger wrote on this subject. Really interesting material.
Cheers,
Peter