After a bit more trial and error, I came up with the following signal route:
Split Y (L100) (R100)
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G amp (L) B amp (R)
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FX Loop L/R |
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Stereo Width |
\ /
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Mixer (L100) (R100)
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Output (Pan = Center)
So, that gives me two mono chains (guitar and bass) to send to FOH.
FX Loop L is my short delay, and FX Loop R is my long delay. With the FX Loop stereo block on my guitar amp chain (panned left), only the short delay is heard.
By placing the Stereo Width block after that, I can snapshot enable the "LRSwap" parameter to swap between the short and long delay.
Now, this isn't a solution to my original issue, because I'm still using 2 blocks and delay trails aren't maintained properly. But, I think it provides a clue for a possible solution.
I wonder if it wouldn't be possible to add an "FX Loop Swap" parameter to the MONO FX Loop blocks. If so, I could save a block while hopefully maintaining delay trails.
(From the Stereo Width example, the more obvious solution is to add an "LRSwap" parameter to the STEREO FX Loop block, but it seems simpler - maybe just to me - to use a MONO FX Loop block for a mono signal chain, if possible.)
I'm curious if anyone else is interested in this, and thinks it is worthy of an idea scale submission.