The problem with the 2.4 and 5.8 GHz bands is, of course, interference. It's especially strong in high density dwellings such as appartment buildings.
The 60 GHz (802.11ad) band would be a good candidate because it won't cross a wall, which means neighbor interference will be non existant. Even windows will attenuate it a lot. The problem, of course, you would need an access point per room. But that means clean spectrum for everyone.
As for lasers, I remember that in the early 90's there was a product called Terabeam that transmitted 10 Mbps Ethernet using lasers. It worked pretty well although it had a weakness, the lasers had to be replaced periodically.
I am now trying a 60 GHz link (Mikrotik Wireless Wire) just to cross a street (20 - 30 metres) and the performance is incredible. Almost the same as digging a trench and laying a fibre. And it's not expensive, less than €200 a pair. Using a phased array with some degree of beam forming you don't even need to aim them very carefully. just use a rule of thumb.