I'm keeping the same trace thickness and layout as the original(somewhat). Since i asked that question i put every trace that i could on the other side which meant i had to use vias on the power traces but now i have a more or less uninterrupted ground plane.
If the vias have to carry any sizeable currents, I suggest using Z-wires on them. A Z-wire is a short piece of tinned single-strand wire inserted through the via and bent over on both sides of the board, onto the traces the via connects together. The wire is soldered to both traces. The wire ends up having a sort of Z-shape when used this way, hence the name.
