Upgrade Build - C-Beam - Y plate questions

I am working on some plans to use Open Builds C-Beam as an upgrade to my current machine. My hope is to increase size in order to accommodate a 2’x4’ piece of ply and make the X/Z ridgid enough to easily handle the Hitachi 12VC router.

My idea was to use plates on the Y-cbeam with the vwheels and connect 20mmX60mm or 20mmX80mm v-slot uprights to the Y plates then connect the X gantry cbeam to the uprights. My reasoning is that it would allow me to raise the gantry by just swapping out the v-slot rails for longer ones.

My worry is rigidity, 1/4" thick aluminum Y plates attached to the gantry c-beam would probably be more ridgid but by how much?