Right now you are simply stacking layer on layer and moving the router further and further away from the gantry, ignoring the fact that overhangs are not your friend. This is the peril of designing a 3d object on a 2d sheet.
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The Y and Z linear blocks could be sunk in to the plate until the rails hit the plate. Less overhang. If they didn't line up with each other then extra metal could be bolted on behind to compensate for the loss. The clever bit would be removing still more metal below the blocks so you approach the limit which is where the rails rub against each other.
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I am all in favour of pushing the limits of the design rather than slavishly following what everyone else has done in the past. I am not building a router so some might say I should keep my fat mouth shut, feel free to tell me where to stick this stuff.
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Your base is overhanging the X axis bearing blocks presumably to hold the X axis screw. All you have to support is a straight push pull, you seem to have a lot of excess metal thereabouts