Sounds good, looks like you have it all planned out. All the plants you listed don't need high light or CO2 so it should be fine (I know you know that!), your tank is quite a lot like what my 70 litre is going to be plant wise, but it will be low-level Brackish. If you get any plantlets from the narrow leaf Java fern then give them to me!
Have you thought about Hygro Corymbosa? They're quite nice too, and could provide some contrast.
Thought about fish yet? Knowing you it would probably be South American Cichlids. You could have dither fish in too.
If you upgrade filters, what are you thinking about getting? Tetratec, Ehiem?
I think thats about it... I think I will dose with Seachem flourish Excel and I will, around 2 - 3 times per week, dose with MonoPotassium Phosphate... I will use mostly rainwater and a small amount of hard tap water so that the water chemistry is Ph 6.8, Nitrite and Ammonia 0, nitrate 0.8 and Phosphate low (can't remember precise amount...)
You have pretty low nitrates and phosphates so perhaps you should use EI, Tom Barr said if you are using Excel as a source of carbon then you add the Pottasium nitrate, Mono potassium phosphate and trace elements mix at approximately 1/2 or 1/3 dosage, if I were you I would use EI, since you have everything needed.
I'm just wondering how did you get a nitrate reading of 0.8?, I've never seen a test kit so accurate, infact most good test kits are normally a fe ppms out, but 0.8 is so precise, what test kit do you have?
So far it sounds great, can't wait to see it setup, and maybe see it for real if I go round your house.
Cheers,
Mike