Since you are too lazy to do the research, I will outline the alt cryptocoins which have made improvements upon Bitcoin core feature set, and expanded upon the uses of block chain technology via adding adding features. I think some of the biggest innovations involve changing the way people think about money. Just as Bitcoin changed the way people think about money, some of these alternative uses for block chain technology will do the same. To be clear, I don't necessarily think these alt coins will overtake bitcoin due to its network effect and infastructure, nor do I think they are all or mostly good investments, but they are improvements upon Bitcoin nonetheless.
Crypto note coins, built in decentralized coin join implementations, stealth addresses implementations, and Zerocoin - Improve financial privacy and protect the end users from the dangers of poor financial privacy practices. Sure, Bitcoin can do some of the things I mentioned but they are not done by default and built into the client. Some people will never fully understand the dangers of poor financial privacy practices, so it is best that the protocol forces them to do it. Most Bitcoin implementations of these technologies require trusted third parties since they are not built directly into the protocol, and/or are not done automatically.
The blockchain as it is now provides a certain level of transparency that is not available with zerocoin. Your argument is that you want to protect people from themselves. However they have the right to make their own choices regarding privacy.
Aliases - making it easy to send and receive currency without the need for long nonsensical addresses. Again, it is possible for Bitcoin to implement this but most solutions I've seen rely on trusted third parties and.are not automatically done within the client.
This contradicts your above point. This is also horribly insecure and opens up a lot of possible scams. (people could make an alias that is similar to a major merchant or to a charity and get a lot of scamcoins as a result).
Confirmation speeds - Some alts have been redesigned from the ground up to incur quicker block times faster than Bitcoin could without being completely redesigned. Some go much further than simply changing a line of code like Litecoin did.
Faster confirmation speeds make the blockchain less secure. A unconfirmed transaction with bitcoin would be more secure then a 1 confirmation transaction with a 1 minute confirmation blockchain (this assumes that the hashrate is the same between the two blockchains, however miners would almost certainly favor the 10 minute blockchain due to a more acceptable expected value of orphans).
Block chain bloat - By using ledgers and truncating the block chain after it reaches a certain size, some crypto have dramatically reduced the amount of data one would need.to download to run a full node, making it more likely people will do so.
bitcoin is not at the point now that this is necessary. Most nodes are run on some kind of server withe the ability to easily and quickly download the blockchain.
Reducing exposure to volatility - Through the use.of decentralized assets that are market pegged to more stable currencies through a decentralized free market, allowing people to hedge against bubbles in a decentralized manner without trusted third parties and allowing the the benefits of cryptocurrency in the former of a stable currency.
This would not be an altcoin, it would be an IOU for the asset that backs the altcoin.
The decentralized exchange of commodities which are also market pegged to the value of those commodities through a decentralized exchange without the need.of trusted.third parties
I am not sure I follow this but I am sure (based on your other arguments) that it is a bad idea
Decentralized asset exchanges which make it easy to receive funding for ideas and businesses without the regulations, taxes, and paperwork the legacy security system requires.
All of the above are good for an economy in small, healthy amounts. If you were to have zero of the above then you would have an economy full of scams and streets full of "danger"/violent crime
Truly deflationary cryptocoins - Whereas Bitcoin will be inflationary well past our entire lives, and the value of which is sustained through the inflow of new money into the ecosystem
the only people who think deflation is a good thing in an economy does not have a good understanding of economics
Decentralized data storage - protecting our data and privacy better than trusted third parties can.
Decentralized programming languages - making it easier to program decentralized programs and services, lessening humanity's need to trust third parties.
A lot of things can be decentralized through the use.of block chain technologies and I'm not going to list them all.
it is not always best to have all functions decentralized. Sometimes it is good to have some central authority that can make changes based on the environment