Well here goes... Aluminium frame router design

[Boyan Silyavski]

I wouldn't put that profile at the back, that limits larger pieces. Instead cut 2 more small side pieces and reinforce the last one of the stair steps at the back of the table, welding a pack of 2 together. Same for the front. may be even one more at the middle. Or reinforce back and front with additional plates.

How long and how wide is the table? may be if you remove what i say you will need adding it bellow, even at front also. Depends on your priorities. Tough i see at the other hand you use a lot of diagonals, so that last may be not necessary.