Wireless Network Design

I'm looking for some advice and clarrification on setting up a WiFi network with a combination of Airport Extreme a Express Base Stations...

In essence what I want to achieve is one universal WiFi network that provides good coverage to my whole property and allows laptops and other wireless devices to travel seamlessly around without having to manually join different networks, whilst also simultaneously having a few static ethernet connections too, which I mostly hope to achieve through the ethernet port of the various Airport Express Base Stations.

I originally brought a series of these devices in the hope of setting them up in a WDS array, but having tried for 2 whole days to do this, spending hours on the phone to Apple Tech Support and reading many accounts online of others having difficulty with this I have given up on that approach. Instead, I have gone back to the drawing board and surveyed my property to assess my options. I live in quite a large old property with some very thick walls and the wiring isn't great and it is split into many sub-circuits, so plug networking solutions are out of the question. Accordingly, I have identified a few places where I could discretely lay ethernet cables and I have tested the equipment I have to check the range in different areas of the house and thus where I would need to place extenders in order to get wireless coverage in all the areas needed.

As I understand it you can extend Apple's Wi-Fi network equipment with roaming (ie extra ethernet connected access points) or using the built in Wi-Fi network extension feature? My proposed setup makes use of both of these options.

I have created a network diagram which depicts my proposed setup and I was hoping others with more experience of this equipment could take a look at it for me and confrim if the equipment will function as I have specified before I actually bite the bullet and make a further substantial purchase of Apple hardware to do so. I have already purchased a Dual Band Airport Extreme and 3 Airport Expresses, which I why I a keen to stick with the apple equipmet so it doesn't go to waste.

Here's what I am proposing:

It all looks quite complicated at first glance but having spent quite a lot of time playing around with the equipment I have and reading all of your online support documentation I believe in theory this should all work…

A few additional and more specific questions:

Will the main extreme base station be able to manage all of this efficiently and reliably?

Will the main extreme base station be the sole DHCP server for the network?

On the main AEBS 1 would I be required/recommended to setup static IP addresses for the various pieces of networking equipment?

With all of these different network extenders and clients will the network performance be compromised?

If I were to want to extend the WiFi signal emitting from the AEBS 2, would I be able to do so through the automatic 'extend a wireless network' tool, or as it was not in range with the main AEBS 1 would it have to be done through an additional roaming setup?

What happens with regards to the channels/frequencies that the various access points are transmitting on? I assume that the AX's that are setup using the 'extend a network' feature will be dealt with automatically by the software, but what about AX1 and AEBS 2, should they be on the same or a different channel from the main AEBS 1? Or should they both be set to Automatic?

Thanks,

Oliver