The roads here have HGV destinations/deliveries, but they are main roads; this causes some routing engines to not be able to route here. Some turns on this intersection also don't seem to be working. Sadly my knowledge of the editor is only good for simple things.

Use valhalla.openstreetmap.de with the truck preset for examples of bad routing through these roads (L3115 / B38).

Relation: 2732357

This restriction does not seem to be there anymore as of 2022 Google Street View:
https://maps.app.goo.gl/uKn4G4QvMwtwCgYZA

This road seems to be incorrectly setup, it allows for routing of vehicles which may be correct but because there is no speed limit it prefers routing via this route.

https://maps.openrouteservice.org/#/directions/10.6550661,51.2440366/Kleines%20L%C3%A4dchen,Rehungen,TH,Duitsland/data/55,130,32,198,15,97,4,224,38,9,96,59,2,24,5,192,166,6,113,0,184,64,70,0,24,3,160,13,128,86,115,13,52,252,1,167,63,98,2,96,5,149,194,6,97,160,110,35,143,38,208,135,0,156,12,154,112,1,193,211,128,118,78,32,232,128,128,1,213,60,8,137,176,229,0,11,202,0,91,92,249,201,41,93,2,0,51,120,0,109,210,225,11,26,60,0,110,72,3,152,5,163,12,154,34,144,230,232,150,232,208,232,136,96,246,120,161,144,6,6,97,176,232,176,254,6,200,0,30,240,6,0,174,6,0,250,152,42,232,137,184,146,132,74,170,234,154,218,160,200,46,16,240,176,57,42,16,54,0,158,238,149,184,160,168,45,5,14,0,178,153,54,234,0,10,205,109,154,254,144,48,8,40,24,218,0,218,0,186,0,190,74,53,117,13,193,104,153,161,11,32,193,208,206,88,32,43,203,203,64,0,0

This off-ramp trunk road has no maxspeed, causing it to be a faster route than staying straight on the trunk road.

It's fixed on my side by using a speed limit of 80, but for cars that can go 120 this off-ramp is still faster to take.
https://maps.openrouteservice.org/#/directions/J%C3%A4dekamp,Hanover,NI,Germany/Am%20Leineufer,Hanover,NI,Germany/data/55,130,32,198,15,97,4,224,38,9,96,59,2,24,5,192,166,6,113,0,184,64,78,0,232,3,96,25,159,1,216,1,96,17,134,128,56,2,101,49,139,92,96,26,1,89,28,54,174,187,22,160,1,148,149,42,149,24,6,226,38,66,141,98,197,27,16,86,210,151,110,189,104,86,27,170,189,97,197,133,81,220,68,7,16,16,0,58,167,129,17,54,28,160,1,121,64,11,107,134,133,11,87,160,64,6,111,0,3,110,139,130,11,13,15,0,6,228,128,14,96,11,70,12,141,14,98,11,238,143,238,141,14,136,134,10,23,141,153,6,230,227,155,14,139,10,150,236,128,1,239,6,224,10,230,224,15,169,133,110,142,89,227,79,128,11,237,212,0,0