I had a rekord 70 check out my first journal in my sig.
With the rekord70 being quite tall you`ll need to upgrade/modify the lights, especially planning to grow riccia and E.Stellata
I think if you planted in blocks like you suggested, since they are all in rows, it would turn into a Dutch sort of layout.
I also presume rotala indica is the red sp. and not the green? If red, then are you sure you want it so central. LOL thats only a thought, it depends how you imgine the rest of the scape forming around it in the aquascape. Its certainly something to think about.
Again, i haven`t a clue what the wood looks like, but how about spreading it a little rather than bunching it! But, i haven`t seen it, it could look cool all bunched at the side. Certainly something else to think about.
Hope that helps.
What i have learnt from doing my two tanks is get and firm idea in your
head of what YOU want it to look like and stick to it.
Good Luck
Chris