Repeater choice and its speed-halving questions

[evnchn]

For simplicity's sake, neglecting the range concerns for now.
There is a AC750 source router with one 5Ghz spatial streams, meaning 433Mbits top speed.
Now, normal people would buy an AC750 repeater and they are sure to have their speed halved. There just isn't enough bandwidth.
1. If I buy any AC1600 or AC1750 repeater, will the repeater split its streams to have an effective AC1200-equilvalent 867Mbits max speed in the repeated WiFi signal? (Edit: I am not hoping for magically more speed, just that there should be a doubling of speed across every range when comparing 2 spatial streams versus 1, hence an increase of range across every speed, right?) If not, does any specific model have such a functionality?
2. If not, then If I buy any AC1200 repeater, will the repeater split its streams to have an effective AC750-equilvalent 433Mbits max speed in the repeated WiFi signal? If not, does any specific model have such a functionality?
Any personal recommendations for the repeaters in question?

 

[L&LD]

No magic math allowed here. The source router is still the weakest link in the chain.

 

[evnchn]

No magic math allowed here. The source router is still the weakest link in the chain.

My bad for not telling you that the source router is actually neighbor's one that I got an agreement to share. He uses the default admin password on an old TP-LINK Archer C2 V1 router and I checked he leaves his 5Ghz WiFi totally unused. I sure hope to strengthen my extender setup so that his router is the weakest link in the chain, just that I am not certain if buying AC1750 or AC1200 will mitigate the speed halving issues. Can you confirm me on that?

 

[L&LD]

No speed halving mitigation possible for a repeater.

The best setup would be to use two routers. One in Media Bridge mode, and connect to the other in router mode (wired).

This will not only separate your network from his, but it will also separate the wireless WAN from your LAN wireless clients. The speed will then be as fast as it can get.

The better the two routers that you use as a Media Bridge and main router the better the experience will be.

Depending on your neighbor's ISP speeds and his actual usage, of course.

 

[evnchn]

Quoting the review of Archer C8 in SNB: TP-LINK told us that when you use the WDS Bridging mode, the selected radio also acts as a wireless repeater. This isn't documented in the user manual and there is no way to disable repeating.

Is WDS bridging capable of doing what the two-router solution is intending to do (no speed halving)?