SO:
A lot of you have mentioned that riding on a flat board is like standing on the hood of a car… it sucks. The board that I used for my first build is curved for flex, but the surface itself has no concave which left my feet feeling incredibly sore after a few rides. I am making decks at the moment and testing designs that I will eventually be selling. Problem is, being the dumbass that I am, I already glued the layers of wood together to make a totally flat surface (did this by following the designs I made and forgetting that I had wanted to create a jig that would give me decent concave). I don’t want to waste this wood and I’ve never heard of a way to safely dissolve wood glue, so I was thinking of adding one more layer of pine on the top that wood be carefully sanded to add a texture to the board which would feel awesome while riding. The more I think of it, the better it sounds because this would mean that the bottom of the board would still be flat making it super easy to add the electronics and enclosure! My only question for you guys is, what do you want? Knowing that I am going to be selling these in the future to some of you (hopefully), I wanted everyone’s input for what kind of texture they like/want. One big concave? Maybe a few small bumps to know where feet should generally be placed? I am willing to try anything, please post suggestions (and maybe pictures) below. Thanks 
You can layer grip tape or grip over foam structures to make artificial concave. This will be better for your application because it will keep your build a little bit lighter. I’ve never done this before, and can’t quite remember exactly what people use, so check some longboarding sites like silverfish longboarding forums for better info!
I’m enjoying the w concave, but I wonder if it places more pressure on the arch of my shoe- I had to change from hard flat skate soles to walking/ running shoes to not get foot soreness on longer rides. Be interesting to see other peoples preferences.
A lot of riders are doing this mod. It really allows an individual to tune the feel of the board towards their personal taste. It works great! You can do foam or layers of gaffers/duct tape too.
Well I’m trying to do something that will look/feel professional, so a stronger foam sounds like a good option. Anything that you like/want/would recommend?
I’m going to be using some studio foam designed for audio applications. Heat resistant and high vibration damping factor too. I have some laying around and it’s very similar to this stuff. https://www.amazon.com/SilverStone-21-Inch-Dampening-Acoustic-SF01/dp/B0040JHMH6/ref=sr_1_26?s=musical-instruments&ie=UTF8&qid=1469604455&sr=1-26&keywords=acoustic+foam It cuts pretty clean, but the best way to cut it perfect is to take a couple of wood clamps and a straight edge, clamp the straight edge down on the line you want to cut and try to do a single pass with a sharp/new razor. Works like a charm.
same here my lower legs and heals where getting sore so my wife got me a pair of skechers arcade 2 trainers,im just back from a 12mile run and this is the frist time i have no pain and the board felt smooth hate to say it she was right…Im not going to tell her.
I really enjoy a very mild W profile without harsh concave on edges.
suttle W with micro(.25") drop is very comfy. i might even go for bigger drop if possible and use riser to adjust clearance.
Completely flat is perhaps surprisingly good for long distances. I have some LDP decks that are flat flat flat.
no… just no. Drop decks are good for long distances. I used a flat deck for a year and my feet ached every time I rode it for more than a mile
I love a good concave. But having a flat underside is heaven regarding mounting enclosures. I used a sector 9 downhill for my first board and it just locks your feet on it.
Progressive concave, tub, w can all be great imo. But the deeper or more radical they are the more important placement and overall design is, and no design suits everyone… so there is no magic… Personally I think with the wide trucks esk8 often has go a wide top mount deck so you have more leverage over your bushings and can retain working geometry closer to a DH/freeride board. Use a foot stop if you need something fore-aft to keep you locked in rather than a drop.