It depends on how you plan to use the products. I am not sure acacia wood burns to charcoal in a coke oven, for instance, and I know I've run into more than one recipe in which acacia logs or planks didn't work. If you want saplings, oak is your best bet by far when compared to the other vanilla trees. Not the small oaks, mind you, but the occasional huge, branching one makes the biggest difference. Even a 2x2 jungle tree doesn't produce as many saplings. For the mod trees, just make sure you can use the products for everything you want to use them for. If you can, FIR. Lots of saplings on those fir trees (but check that the cart cuts high enough, because it might not).
Now I gotta try setting one of this up with some cheated-in silverwood saplings, and then watch what happens with all the nodes. Probably best to do that in a test world.
Now I gotta try setting one of this up with some cheated-in silverwood saplings, and then watch what happens with all the nodes. Probably best to do that in a test world.