I have used D subs in many places for wiring and they work quite well (be sure to limit current to 3A per pin). I would suggest that you not use the solder type which is very difficult to fabricate and will lead to failures in the joints.
A better solution is to used the machined pins and an appropriate crimper (SteinAir has a good one at a reasonable price). The gold plated machined (Milspec) pins are about 30 cents each in quantity but are very reliable and easy to use. The connector bodies are very inexpensive...I buy them at the computer supply outlet Altex in Austin.
Also D subs can be easily connected by using nuts specific for this between the connectors (small 4-40 1/4" tall nuts). And if space is tight, you can forego the shell covers.
In the specific case of the trim wires (26 ga), I have had good success with using the male and female pins directly plugged together without the connector bodies. The normal crimp pins are not sized for the small servo wire, so you have to double the wire in the pin. Use shrink tubing to insulate and hold the pins together and if you have to disconnect later, just cut the shrink off...
And as normal, all wires need to be bundled and tied with tywraps or lacing cord to eliminate any vibration.