Firstly set up a BQM at thinkbroadband.com - this will give you an insight into what is happening with the signal coming into the property, it will take a few hours to get any kind of trend showing.
Type 192.168.0.1 into your browser URL bar and press enter. When the page appears DO NOT LOG IN but click ‘Check Router Status’. Copy and paste the contents of each tab onto here, a Guru will be along in the not too distant future to decipher the info.
Your downstream power levels are somewhat on the high side, but there are no log entries to indicate that this is causing any issues.
The important question to ask is, in your original post regarding speed, how were you measuring it? Was it a device connected directly via an Ethernet cable - which is the only reliable method, or over a device connected via wifi?