Hello ladies and gentlemen of Aquatic Community. I am new here and this is my first thread aside from my introduction. :)

I am in the process of designing and building a rack to house several aquariums in my basement. I was just going to set up 1 tank but then I remembered how there are so many kinds of fish I would like to keep. I have kept many kinds in the past but have been on hiatus for the past couple of years due to moving too much to keep aquariums. I have a few ideas of how I would like to build the racks but I would love to have input and suggestions from the experts and newbies and everywhere in between. Especially people who have experience with racks. As of now I am not sure exactly how many tanks I will have but I will get as many as the wife will let me have, mostly ranging from 10-20 gallons. I am hoping nothing larger then a 40 breeder.

a few things to consider before suggestions

1) all fish will be small peaceful species. largest fish will be apisto's or GBR.
2) I have a reverse osmosis unit so water chemistry shouldn't be too much a problem despite the fact we have liquid rock here in Edmonton.
3) I would love to rear fry if I am ever so fortunate to have the opportunity. This is one of the major reason for multiple tanks. I have had fish spawn many times on me in the past but never had the means to raise any fry being always limited to 1 tank at a time. To me this would be the most rewarding part of the hobby.
4) I would like only 1 community tank and the rest to be species tanks, aside from amano shrimp in every tank.

So with that being said I am hoping people can suggest either
a) species of fish to keep - They must be small and peaceful. Breeding in the home aquarium is a major plus or any kind of fascinating behavior
b) tank sizes for specific species - input on already selected species would be great!
c) tank configurations for the aquarium racks - this would be super awesome to have suggestions for.

So far species I know I would like to keep for sure in their common names:
German Blue Rams
Cherry barbs
Celestial Pearl Danios or Galaxy Raspboras
any dwarf species of corydoras.
Amano Shrimp
Cherry red shrimp

All tanks will be using sand and or fine gravel as a substrate with hamburg mattenfilters or general breeder sponge filters. Dirftwood and low maintenance plants also like java ferns and mosses.

As for rack configurations I have a few ideas in mind. Tanks that seem to fit nicely together and could easily build 2 columns of these.

40 breeder on top with 3 15 gallon tanks underneath turned sideways. I think the 40 breeder would well accomodate a breeding pair of gbr's or apistos with some dithers and the 15 gallons can be species specific or for rearing fry. Of course I would need 2 of these setups at least or else 2 rows of 15 gallons.

20 gallon long on top with 3 10 gallon tanks underneath turned sideways. I think the 20 gallon long would be sufficient for a pair of dwarf cichlids but I am not sure. I would like to keep them with dithers for their comfort. Also think the 10g tanks will be a little small for my chosen speciess so far. On the side note I have a few free 10g tanks coming as donations from local aquarists I had dealt with in the past.

Aside from this I really don't have any other ideas. Space isn't much of an issue but I would love to create the illusion that it is smaller then it is for the sake of the wife :)

I know this is a lot and kind of all over the place but I am on meds recovering from a surgery a few days ago so forgive me but I am going crazy sitting here with nothing to do :P

Thanks in advance,