Goals for My Network - Your Input/Suggestions Solicited

I have a fairly simple home network. I want to make it better.

I have successfully installed OpenWRT on my routers.

Goals

  1. Create a reliable wired and wireless network on a single SSID using both 2.4 and 5GHz radios with fast/seamless roaming (or at least good wifi speed almost anywhere in the house/garage).

  2. Minimize browser ad clutter/annoyance.

  3. Minimize the number of devices ignoring/bypassing local DNS.

Proposed Hardware/Software (already have)

  1. One router and two dumb access points all running OpenWRT. (House has Cat5e network wiring. Several unmanaged switches are in use.)

  2. Pi-hole running on Raspberry Pi with Unbound. DNS query logging per client.

  3. Configure hardware to force DNS queries through Pi-hole.

I have a working network/router (non-OpenWRT) and Pi-hole now and that is my default/backup system. What I'm proposing here, and working on now, would replace that system.

I have already spent many, many hours reading as much as I can, and trying to get some of this working without much success. I always have to give up and go back to the backup system. I am finding that many tutorials, despite being well-written, may be outdated and/or no longer work.

For example, there is this one:

The first thing I found was that the code to disable ipv6 does not work. Are recent releases of OpenWRT not compatible with that code? I assume it worked in the past?

Another example would be:

I could not get this working either. Dig output/results were the same with or without these configuration changes to OpenWRT. Should this work, or are recent changes to OpenWRT/Pi-hole causing this not to work? Is there another/better way to accomplish this?

Are my goals achievable for a non-expert (but reasonably tech savvy person)? I really don't want to abandon the OpenWRT approach. I just don't know where to look or what to try next. Any comments or suggestions would be great. Thanks in advance!

Regarding the first link with the post in Openwrt forum, it really depends on which version you are running and which router compared to the version of the writer.
For the second link, it is not affiliated to OpenWrt forum or wiki, so I cannot comment.

Like @trendy explained, docker is needed for running pihole on OpenWrt, so you'll probably need a hardware that supports docker and has enough storage (about 400MB), and so it's mostly RPi and x86 hardware. On the other hand, there is adguardhome (which is a smaller) provided in the repos/softwares.