I'm against this for a reason: Adding all these shapes would probably require an increase in available block IDs which would result in increased data size per block which (if I'm not wrong) would result in a larger ammount of traffic for servers. Yes, the dev team stated that an increase in data ammount per block to achieve a higher ammount of available block IDs could be done if needed, but I don't think this is the case of need because the drawbacks outweigh the good things. Additional design choices are nice, but not at the cost of worse performance, especially for people with weaker computers.
Another problem this would raise is: Where do we stop? If we add a ridiculous ammount of shapes, how can we reasonably argue against the implementation of even more shapes (like a 1/2 slab which has 1/4 empty space to both sides or a 1/4 slab having 1/2 space to one and 1/4 space to the other side. and now combine these with other shapes).
I think the current ammount of shapes gives us a lot of creative freedom, the shape I'd see the most reason for adding (although I think it's not really neccessary) would be a counter-corner, basically what a hepta is for a tetra but for a corner.
Even if the devs would want to implement this, I'd say it should take low priority, because I somewhat agree with
Raisinbat that gameplay features should be of highest priority.
Logic impact on gameplay: Chaindrives