Is this a design that is acceptable ? Basically I am building a small box that will collect water pumped up by the condense drain I will put this up in the ceiling in the furnace room just between the joists The pump will pump the water in the box. It the 1/2" does not have a proper slope this will compensate for the lack of it as the water level increases in the basin it will force the water to drain through the pipe

This is intended to reduce the stress on the water pump which is currently having to push twice to push the water surplus through the existing setup. This is partially because I went all the way to main drain with a 3/8" pvc tubing and I think that is bad. When the pump stops the water trapped on the vertical segment between ceiling and joists level has nowhere to go and it drains back in the pump collector box. That in turn makes the pump start again and the cycle repeats till sufficient amount of water is finally pushed through to stop this even when the water is coming back

The alternative, in case I manage to give it a mild slope is to use this setup