For washing waterproofs and softshells I use Dripak liquid soap – Available from larger Tescos, and I’m sure loads of other shops.
Much cheaper than Techwash, and does exactly the same thing (i.e. doesn’t strip the DWR coating off, or “wet” the fabric). You still need to use a DWR replacement like TX Direct every 5 or so washes though.
“Normal” non-technical layers, just get a quick rinse in the sink before going in the washing machine, to get the worst of the caked on mud off.
Edit: Also, “top tip” (!), from experimenting with my waterproofs, it seems that when using a wash in DWR replacement, if you turn off the rinse setting on the washing machine, it gives a better, longer lasting coating to your clothing. I’m assuming the rinsing washes off some of the coating you’re trying to apply…