All/any devices connected to Lan 1 Port receive 1000Mbs - correct?
And no devices connected to Lan Ports 2, 3, and 4 receive more than 150Mbs - correct?
No dependencies on the Ethernet cable being used. Meaning that a cable used with Lan Port 1 performs at 1000Mbs but when connected via Lan Port 2, 3, or 4, is limited to 150Mbs.
One thing that I noticed in the TCG300 specs:
"Multiple Client Support: 254 (router) 32 (Bridge)
That 32 "limit" (?) may be related to the downstream errors on Channels 1 - 24. I simple do not know and will defer to those who have knowledge and experience with bridging in environments such as you have described.
I am still not sure about the overall connectivity involved and the relationship between performance and the number of users (75 or greater than 75).
And much of the TCG documentation that I am finding is not in English and difficult for me to even reason out some of it.
Not sure what else to suggest.
some extra info on internet maybe usefull

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