What Litecoin did was find markets so you can buy and sell with it. That is why it is worth so much compared to all the other Alt-coins and that is why BTC is still worth more then LTC it has a larger marketplace from which to spend your coins.
Everyone seems to be fixated on the technical aspects of the coins but this isn't what is ultimately going to provide lasting value to them. They need to have markets other then just being traded for other crypto-currencies. If that is all they are good for they are speculative value only and their value will go poof as soon as the speculators move onto something new.
You are right, but in the early stages a huge reason people mined Litecoin was because it was ASIC-resistant. If Litecoin was another SHA-256 coin I don't think it would be where it is today.
Aside from only adding or changing trivial things, the problem with these new coins is they are based on the same code as Litecoin, and being scrypt, as soon as they aren't profitable anymore miners go straight back to LTC.
LTC didn't have to deal with this problem because it was one of the first scrypt coins. And also, there weren't clones being released daily back then. That alone allowed it to grow more naturally like Bitcoin. My point is it is very hard for a lot of these coins to co-exist with LTC around, you will have a very hard time convincing miners to adopt your coin just by changing some parameters around. Simply having faster transaction speeds isn't enough.
Merchants won't adopt a coin on the basis of transaction speeds alone either. I would be extremely skeptical of the security in WDC if only a small % of miners are backing it. I have seen people on here say miners don't matter, which is just ridiculous... in order to prevent attacks you need a large amount of STABLE hash power. Both Bitcoin and Litecoin had a huge amount of miners on-board before anyone started using it in markets.