Some comments on the issues you've raised.
1. If you're still paying $300+ monthly for 100 GB, then you should switch to one of the new flex plans that were introduced a few months ago. See the thread "New Flex Rate Plans for Mobile Internet" in this forum.
2. You don't mention which RocketHub ZTE model you have, but you can certainly change the IP network from the default 192.168.1.0 on the ZTE 28B model. In any case, you can use any of the other 254 networks in the 192.168.x.0 address space for your internal networks (assuming a 255.255.255.0 mask). You don't have to use the 10.x.x.x address space, but there's nothing wrong with using that address space either.
3. Notwithstanding the static IP issue, you should be able to connect all your remote access devices (to a maximum of nine) to the Ethernet ports and WiFI network of the RocketHub, thus avoiding double NAT. It's not necessary to disable the WiFi on the RocketHub if you're using a downstream internal router. (BTW, I've always assumed that the device connection limit of ten is because of limited RAM in the RocketHub devices.)
4. To avoid the cost of a static IP and the problem of port forwarding, you could set up a computer on your internal network that has access to all your remote devices, and then use Teamviewer (free for personal use) to connect to that computer from the outside world.
5. I have no personal experience with simple range extender devices on my internal network, but I have had no issues with a secondary router, a wireless access point and a switch all attached to my main internal router (which is not an Apple product, so your mileage may vary).
It's true you cannot turn off the NAT on the MF271, but you can avoid double NAT by turning off NAT on the second wireless router and only use the second router as a wireless access point. In that case you have to connect the Ethernet cable from the MF271 to one of the LAN ports of the second router, not the WAN port, and turn off the wireless feature on the MF271. The downside is the MF271's router features are much weaker than most dedicated routers so you might lose some critical functions you depend on. But this is one way to avoid double NAT. The plus side is that you circumvent the 10 wireless user limit and gain a wireless AP with much more powerful signal and range.
Using the MF271 as a router for my network it burned out in 3 months. I confirmed on the phone with tech support today that my 271 was likely overloaded because its not meant to handle as much routing as i was doing. About 30 devices, most hard lined to a switch.
This begs the question, why have a router that can't be bridged if it can't handle routing?
You may say, "It can handle routing, just not on that large a scale". To which i say.. IT CAN'T.
if it can't handle 30 devices while it's wifi isn't even on and it's only being used as a router and modem... IT'S NOT A ROUTER!!
Hello... I was reading your post about the ZTE MF271. I would like to hook up a security camera and monitor it with my Iphone. Normally this requires that I can access the MF271 Wan IP address and possible port forward the camera. Has anyone been able to do this succesfully ?
Yes, it will work,
How I did it, was to use a separate router to reduce the load on the slower MF271
First, I got a public routable IP address from Rogers. Then I set up the LAN as 192.168.1.255 with all radios off. Then had my main netgear router hooked to the mf271. Port forwarded all ports to the netgear. I then used the netgear as both firewall and router for all devices in the house. With some fireall rules and port forwarding on the netgear, I had cameras, media, etc available to me wherever I am via mobile.
I don't know your knowledge level, but I can help you if you get stuck.