Are there paperwallet generators for all ALt coins

Hi There,
New to Crypto but have a question that seems to be more technical than I thought it would be.
I intend to purchase a few different coins. Some main some alt. Purchase is for the long term and for my goals I have decided paper wallet is the most secure and best way forward.
I have an air gap machine, and developed a process in which I can ensure that wallet generators such as walletgenerator.net and myetherwallet can be safely transferred to the machine.
Some of the coins I wish to invest in are not supported by walletgenerator. so I have a couple of questions and the first few get to the guts, but the last question is more fundamental education for myself.
1. I have 13 current coins I am looking at, some of these are ERC20. Can these coins be stored on an Etherium wallet? As I understand they are built on the ether network, so as long as I have one paperwallet for each coin it should work. Right????
2. Do I have to approach each project in order to find out if they have a paperwallet generator? Right now I have 13 I am looking at. maybe I find another 4 in a months time…. I would rather make say 30-40 wallets on a lazy saturday afternoon, use some now and some later.  I would rather ensure that I follow the same secure process repeated to generate multiple wallets than to do this adhoc. Plus my process for generation of wallets include a full system install at the conclusion. Can’t be too careful.
3. And this is the educational question which may answer or explain the above two.

When I go to walletgenerator.net, and select Bitcoin create a wallet, and then select dash and create a wallet, what is the actual difference between the two keys. They both appear to have the same number of characters, so the blockchain (after my purchase transfer process is complete) is populated with my paperwallet details and nice a safe on the network. Why are 197 currencies supported? What is the actual difference between the 197 and the 198th coin?