hi,
It would be nice to have some kind default sink for fluids, a fluid request mk2 pipe and a fluid remote orderer pipe.

How about a second Tab for the Remote orderer, featuring fluids? Plus an additional connection to the Fluid remote, so One Remoteorderer could handle both Liquid and Item Requesting.
That way Players arent put under the pressure to have an extra Item with 99% same functionality in their Inventory!

BTW dont we allready have a Fluid sink? Dunno what its called but im sure I used something like that before!

This is not about the hand held orderer, it is about the pipe you attach it to. Using the same orderer/pipe for items and fluids makes little sense - you probably don't want to request your fluids to your ender chest.

The basic fluid pipe can sink fluids, just like the basic logistic pipe can items. The problem is that it has no default sink setting.

Is the tinker's construct smeltery also a special case?
Also a default sink is nice if all you know is that a liquid will enter your network, but you have no idea which.
So it might be a good idea to have 3 small tanks with default sinks to ensure that extraction pipes don't clog up the moment they encounter an unkown liquid.

"The problem is that it has no default sink setting."

Correct but I think it is intentional. In terms of items default routing makes sense since we have an item storage that can accept different type of items (such as logs and sticks) however, we currently do not have (and I hope we will not have) a fluid storage that can accept multiple type of fluids (errm, do not bother me with ExtraCells and AppliedEnergistics 😄 that is a very special case and LP may or may not want to handle it).

So default route for fluids is not makes sense in this environment.

TConstruct smeltery is a special case since as I know the smelting tank is not implements IFluidTank (but I will check it tonight). Any normal IFluidTanks can contain only one type of fluid because the API does not support draining specific type of fluid and FluidTank reference implementation checks if the inserted fluid is same as the tank already contains.

I do not use the fluid part of the LP very often, but I think if you leave basic fluid pipe unconfigured and connect multiple pipe to multiple empty tanks, they will slowly become filled w/ different type of liquids. However I do not know there is a quite much cases where you do not know what fluid will enter into your LP network because fluid is not generating randomly in pumping devices - usually you have a lake of the fluid and you want to pump it out.