the shaper rate is the gross interface rate, with these setting you can at best expect the following TCP/IPv4 goodput (what typical speedtests measure) of:
184000 * ((1500-20-20)/(1500+35)) = 175009.77 Mbps
85000 * ((1500-20-20)/(1500+35)) = 80846.91 Mbps
as you can see in the upload direction your tests are already close to the theoretical maximum. Sure the downloads seem to under perform a bit, that might (or might not) be related to the CPUs in your router which might be overloaded or might try to use powersave features which interact badly with SQM, you could try the performance governor.