I would go for a tank similar to what i have now but with less Severums

...
Rotkeil Severum (because these guys max out at 8"... standard Efaciatus Severums...ie Green, Gold, Red Spotted can get to 12")
Blue Acara
Pair of Bolivian Rams
8 x Shoaling fish (something bright, colourful, won't fit in Adult Severums mouth...would avoid Barbs because they are nippy, and Tetras would fit in the 'Amazon' theme with the rest of the fish)
And offload everything else
Obviosuly don't rush out and stock all at once...
I would stock it like this...
Severum first (you could probably get a Rotkeil off this forum somewhere, i will be selling some in a few months, Star is breedign them etc)
Then grab your Rams (don't get Germans, they are a pain in the nutz, despite looking pretty...unless you want the hassle of keeping them in permantly warm discus like water)
Get a small Blue Acara next...don't worry about sex (i bought mine in December at 1" and it is now 5"... so they grow pretty quickly)
Grab your dithers at any time.
For Plants, attach some Anubus to bog wood...mine has doen pretty well, if the Sev starts to eat it, trim off the eaten leaves, let the roots/Rhymzone stay in the water and let the leaves poke out of the tank for a while, they grow rapidly like this, my Anubus Bartoni has got gigantic in a month or 2 using this method because they are not a true aquatic plant, they are a bog plant, meaning they can live in and out of water.