Access Point Woes WRT3200/ArcherA7 & wireless links

I'm trying to figure out the best way to set up my home network now that I've finally found the bandwidth I've been seeking with the help of SL's dishy. I'm trying to accomplish this using the following topology.

                          mainwifi2.4g/5g)&(if possible>)guest2.4g                            mainwifi & guest2.4g
main_Pi-router__________________________wrt3200acm_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-Archer A7
|location|            ^GigE^       |location  | ^ wireless to outbldng^ 
|basement|          (in wall)      |main floor|  (workshop ~250ft link 2.4ghz several walls)

              Ethernet to this bldng. will requiring burying a line and that's not happening for a while(I'm lazy)
              The main router is located in the basement due to the backup DSL line and future
              fiber connections coming in here. Also my switch & home runs to the patch panel are here.

I just acquired a wrt3200acm as well as a wrt32x for cheap because some very 
nice idiots used the wrong power supply and didn't know to remove the diode 
when it turned into a wire(aka direct short to ground at the barrel plug). :smiley:

The linksys doesn't seem to like it when I attempt to configure more than 1 wireless network on each frequency/radio no matter what I try. It also doesn't work well when using one as WDS AP. Attempting to use either radio with the aforementioned settings results in a major bandwidth reduction at the client devices for both radios (12-20mbps total). I've tried quite a few different ways to get it to work, but haven't yet read anything about why it happens. I blame either the drivers, or me for trying to do something the hw is not capable of... but it is what it is. If there's a fix someone could point me to, or if someone could explain the details of why this happens, or tell me what I'm missing to allow it to work I would be grateful. The A7 doesn't seem to suffer from this although Idk if using the 2.4ghz for both a client connection and guest+main access points possible or advisable since I haven't attempted this.

Since the wired AP needs to have both 5ghz for bandwidth and 2.4ghz for connecting the shop AP's client and for longer range to support mobile devices I'm thinking that setting up a tunnel between the main router and workshop AP will be the best option?? If I'm right about this, what would be the best way/tool to accomplish this? Will I need another wireless interface for the client connection since I intend to mainly use the 2.4ghz for the workshop access point?

Guest and secured wifi access on the shop AP is the primary goal right now. Roaming between the home/shop is definitely second, but would be really nice. Not trying to ask for hand holding, just point me in the best direction if you have an idea of how I can accomplish this without wasting too many more hours figuring things out :grin: :grin: