Upgraded, but I'm still getting slow WiFi and LAN speeds.

I've recently upgraded to 600 Mbps and have gotten equipment rated for higher speeds, but I'm barely hitting 100 down on WiFi and maybe 150 on wired. I've switched to a less crowded channel, but I'm still barely hitting 200 if I'm lucky. My current equipment is an Arris SB6190 & a TP-Link AC1750 which are both adequate for my plan. I don't have any splicers and am using the required cables for them. Is there anything else I can do on my before having to call for a tech?