Hi,
Well, there are several issues involved and I think you hit the nail on the head with the term "marketing". This is a problem because vendors want to separate us from our money, so all kinds of claims are made and the truth of an issue always seems to get trampled and buried beneath their feet. Subsequently, a false house of cards gets built right on top of the debris by convincing you that there is some property of material that is crucial and that their products have that property you need. So we really have to excavate in order to unravel the pieces of information that are actually useful.
In the first place, EcoComplete is not a terrible sediment. It's made out of clay. Clay sediments are the choice of aquatic gardeners for a very good reason, and that is because clay has a property called Cation Exchange Capacity, or CEC. Without getting too bogged down in theory, it's sufficient to know that the reason that a sediment has an effect on the water parameters has to do with this CEC property. CEC allows the soil to pull nutrients from the water and to pass them on to the plant roots. So even though the clay itself is inert it can sequester nutrients from the water to the plant. It's therefore no big deal that EcoComplete is basically inert.
Compost and other types of organic sediments also have very high CEC as well as being naturally loaded in organic forms of nutrients. However, they can become messy if the hobbyist engages in a lot of replanting and of course there is the issue of color, texture and aesthetics, which is more than just a trivial concern.
I actually have used EcoComplete many times, not only because of the CEC but for other properties of the sediment that I value. For example it is a heavy clay so that it does not float around the tank. It sinks and stays at the bottom. It does not cloud the water, making it easy and carefree to vacuum and clean in situ. What I am strongly opposed to about EcoComplete is that it is marketed as something that it is not. It is NOT a rich sediment and it is NOT fortified with high levels of nutrients but it is marketed that way and it is priced as if it were an enriched sediment. Have a look at the thread
Flora max V Eco complete
The other issue that I find disturbing is the propaganda that somehow, it is really necessary for substrates to either buffer the water against pH variations or that the quality of a substrate is determined by it's ability to affecet the water's pH. So, like you, many are disappointed for one reason or another. The truth of the matter is twofold:
1. Even if a substrate does have an effect on the tanks water parameters, the effect is only temporary. After a few months the effect is negated by other chemical forces occuring in the tank.
2. Generally, plants and fish really don't care too much at all about pH. What they care about, more than anything else is the ability to breathe. Oxygen does not dissolve very well in water so fish have a very difficult time actually breathing. One of the main issues that negatively impact the ability of Oxygen to stay at acceptable levels in a tank is dirt. People don't change the water in their tanks often enough because they become slaves to the idea that they must keep their parameters as stable as possible, and in so doing allow organic waste to accrue in the tank which robs the tank of Oxygen. In a planted tank the plants exhale Oxygen during the day but again, this amazing fact is often ignored and it goes unrealized that the more you do things to help the plants grow, the more things the plants do to help the fish stay healthy. Whaterver negative impact there is from not maintaining a certain pH is overwhelmingly compensated for by having an increased Oxygen availability. In my tanks, Oxygen availability is given top priority. Whatever procedures or actions directly or indirectly yield a net increase in Oxygen are followed and everything else plays second fiddle.
Therefore, in my honest opinion, the issues that you seem to be disappointed with are not that important in the greater scheme. So what if EcoComplete is not enriched with nutrients? Just add nutrients which are cheap and easy. These nutrients will not only feed directly into the leaves, but they will find their way down into the substrate and will be passed on to the roots via the CEC properties of the EcoComplete. Keep you tank clean by removing fallen/floating leaves and other organic debris immediately and do not allow them to rot in the tank. Vacuum the substrate occasionally to prevent overloading of the substrate with rotting waste. These simple actions, if performed relentlessly will improve the Oxygen availability of youre water and will improve the health of your tank far more than worrying about pH this or pH that.
If you suffer from insomnia have a look at these threads discussing CEC:
viewtopic.php?f=17&t=21585
viewtopic.php?f=21&t=21198
viewtopic.php?f=17&t=21739&p=222426
Cheers,
I would suggest getting a t5 HO luminaire possibly a 2x24w if you are going for carpeting plants 
