Updating our mobile-based Internet connection

[rangor gubbins]

Our home Internet access is via a 4G teltonika router with sim card. The aerial is on the roof above the chimney stack, then a 25 m SMA cable (it's two cables joined together) into the loft connected to the router.
There's now 5G signal available outside the house, so I'm thinking about upgrading our aerial and router to 5g. Whilst I'm doing that it seems like a good moment to think about better cable routing.
My questions:
1. Any recommendations for 5g routers? Our teltonika RUT 950 has been excellent so I'll probably just go with that brand again but there's a few models to chose from and I'm not sure what's best for my scenario.
2. Any recommendations for 5g aerials?
3. How much affect does the length of the SMA cable make on signal to noise ratio? Would it be better to have a short SMA cable but potentially have the router outside with an ethernet cable running into the house? Or have router inside the house but a long SMA cable with a join? There's a possibility I can reroute the SMA cable so that's it a shorter run into the loft and keep the router inside.

 

[rangor gubbins]

Thanks for the ideas. I didn't know that was an option. I've got a zyxel access point and a switch, so adding a router to the network makes sense perhaps.
I'll have to look into what will give best signal performance, a dedicated aerial or a router with in built aerials.
My worry about sticking a router with inbuilt aerial high on the roof outside is access if anything needs fixing or replacing, e.g. Sim card, hard reset, or other errors. It's quite a major job to safely get up onto the roof.
With separate aerial and router I can put the aerial high up but have the router below the soffits which would be much easier to get to.