4g Router recommendation please

Hi,
Long time reader and first time poster here.

Firstly I appreciate that the title is vague for my own liking, so here is some background.

Im UK based, in the north west and in an area which according to the network operators coverage maps indicates that I am in a coverage area for 4g mobile broadband.

I have recently switched from ADSL to mobile broadband and for the most part, am living quite comfortably with the change. I have switched to EE and using their 4GEE WiFi Mini which meets the most basic of requirements, however is lacking a world of configurable settings and monitoring options which I do like to have, as well as options around external antenna.

I have a few drop-outs each day for <60 seconds which at a push I can live with. Heres the clincher tho, I work from home and remote into the office to do my job, which requires me to be connected throughout the working day. Any outages more than 10-15 minutes would result in me having to jump in the car and complete a 45 minute drive to work and finish the working day there, which I would prefer to avoid.

So what I am looking for is to provide a significant improvement in download speeds as well as latency. (The kids arent impressed that Dads broadband doesnt really cut it for online gaming) Upload speeds Im not too concerned with as thats not something I have any need for.

My general usage is remoting into work and teams calls throughout office hours, followed by streaming music/Netflix / Amazon 4k on a couple of TVs with the occasional downloading of ISOs.

Im around 275 Meters from the mast I spend most time connected to. Because of this I am keen to look at routers with external antenna connectors with the obligatory antenna options, since the antenna side is not something I have looked at previously.

So after the above ramble, Im looking for a router with the following requirements / preferences, but very happy to take on board any suggestions or relevant questioning of my logic or lack thereof 

  • 4g only - Not 5G

  • Firmware that will allow advanced features such as band locking and or avoidance particularly multiple band selection

  • Nothing below Cat 12 please as I want this to be an investment for a good couple of years. The router I have now is Cat 4.

  • Download capability of 300-600Mb L1 (I have no expectations of achieving 50% of the 300MB however if I can get close to 50Mbps or higher then that would be great

  • SNMP monitoring options where I can pull throughput stats, RSSI, signal strength, etc.

  • external antenna options is a must

  • Ideally something that is mains powered but can be powered from 12V/9V/5V DC via an additional regulated supply so I can throw it in the car/caravan if and when Im away for a week

  • Brands wise, I have been looking at Huawei and Teltonika, as well as TP-Link.

  • I have no issues with how this looks as long as it does its job.

  • Finally, budget - As always cheap as possible from a major brand. Ideally under the £100-120 mark for router alone, I can add the antenna on later.

Im not looking to make the leap to 5g given the bickering that the operators are in the middle of since this is affecting rollouts right now. Im not in a coverage area and dont expect to be in one any time soon.

Finally, thanks for giving up your time to read the above, and I look forward to any suggestions.

Cheers
Dusty

Technical bits

I generally connect to 1 mast, however I can see that on occasion bounce between 3 masts.
Again across these masts Im mostly sat on band 3 but ocasionally end up on band 20.

My regular speed test type results float between 2 and 8Mbps down with 1-3Mbps up and latency generally between 50-80ms.

My primary mast is Cell ID 3705344 LAC 11291 which I dont mind sharing.
When checking network stats across other operators using OpenSignal etc, which I appreciate is a wet finger in the air, is showing EE at around 45-50/8-10Mbps with the next fastest operator being 12/3Mbps.

I live in a generally flat area with nothing impeding LOS to masts if I was to mount an antenna in the loft or on the TV Aerial etc, so would expect some reasonable uplift in performance just by doing that. Sadly my current unit doesnt support external antenna.

Im looking at putting together an idiot guide around this sort of thing for my own reference, but can also post back into this forum if there are any takers interested?