Substrate - Cory's much prefer sand, it is easier on their little noses, and they siphon it through their gills to get food. I find sand is a must for cory's. Sand also doesn't hold as much dirt and left over food as gravel does. Any dirt will simply lay on top, which is a breeze to vacuum up.
Plants - Go planted! It is so much fun, and your tank will look incredible. Just do your research on what plants will go well in your tank with the equipment you have. (CO2, low light etc)
If going without CO2, I have had great success with Hygrophilia Corymbosa, Hygrophilia Stricta, Hygrophilia Polysperma, Vallis, Java Fern, Java Moss, Amazon Sword, Tropica Sword, Red Ozelott Sword, Broad Chain Leaf Sword, Anubias Nana, Cryptocoryne Wendtii and Crypt. Balansae.
Fish - I would get rid of the silver dollars, they will get too big, and if you want Neons, they will more then likely eat them. I have a feeling they will pick on the cory's as well.
- The rainbow sharks, albino included, need to go. They are far to aggressive, and need a lot more space. They are sure to kill the cory's.
- Same goes for the Silver Sharks. They will grow far too big, and kill other fish.
- I'm not sure about the chinese algae eaters, I don't know much about them, I have a hunch they can be quite aggressive.
- Clown loaches need to be kept in a school of 6+, they're a very social fish, but they will also grow too large for your tank.
- Khuli loaches will be fine.
- The remainder of your fish should be fine.
- Maybe look at cardinals, instead of neons? I think they're much prettier.
I find the rule with cory's is, don't have anything too aggressive in there with them. They're sensitive to stress, so you don't want anyone nipping their fins and chasing them around the tank.