Sanity Check on use of M4100-26G switch

Please someone sanity check my intended use of the M4100-26G switch...

We have a COX business route wirth the standard 2.4GHz and 5.0GHz WiFi and 4-port RJ-45 Ethernet ports (specifically Cisco DPC3829).

It has an internal IP address of 192.168.0.1/255.255.255.0.

I have purchased a M4100-26G switch within which I I have configured 3 VLANs 1004, 1010,1016.

Each VLAN has 6 of the switch's Ethernet ports: 1004=(0/4-09), 1010=(0/10-0/15) and 1016=(0/16-0/21).

The default VLAN 1 is all other ports.

The IP Address of the M4100 switch is 192.168.0.234.

I assigned  IP address subnet 172.16.0.0/255.255.0.0 to VLAN 1004, 172.17.0.0/255.255.0.0 to VLAN1010 and 172.18.0.0/255.255.0.0 to VLAN1016.

And I setup up static routes pointing each of the VLAN subnets to the COX router's 192.168.0.1 router/gateway as the next hop.

What I'm tring to do is the the switch to setup three different IP address subnets and have the COX router, route the 172... networks of the switch to the outside world.

Am I smoking poorly grown dope or am I on a valid approach? 

VR/JW