Good points, but I would like to correct you that EOS is an application platform itself and does not run on the Ethereum platform. Only the current EOS token is being distributed on the Ethereum platform because they're trying to keep EOS hands off, maintenance-free during development.

That's mostly what I want to say. More description below of my understanding if you want to read:

1. Why have a token on Ethereum platform?

   • This was a decision by block.one for optimal development progress. If they launched EOS platform and distributed tokens on the EOS platform, development speed will slow down dramatically due to maintenance of the platform. Making changes at that point becomes more difficult because once applications start using the EOS platform, EOS has to keep their users in mind for every change it wants to make.

2. Then why have ICO over 12 month period now instead of after launch?

   • The current 12 month ICO is just a preliminary spreading of the seeds. Other ICOs do it too, crowdfund with little more than a whitepaper and promises. At least EOS is backed with years of knowledge from block.one and technology of Bitshares and Steem. They don't need the money and its purpose is not crowdfunding. Its purpose is to broadly distribute the tokens for a fair, decentralized platform. It's also to provide publicity of the platform and time for the community to be familiarized with the project. Someone could technically write an application using the EOS platform before the launch and have it ready by the time EOS is launched. The ICO lasts a year because it mimics mining and makes it harder for whales to snatch better investments than everyone else.

3. Will it be an Ethereum killer?

   • No one can say for sure. EOS, being an application platform, directly competes with Ethereum, but it depends on the technology of each and users of the platforms. If companies adopt the Ethereum platform for their smart contracts, but discover limitations, then discover that EOS does not have those limitations, then yes, EOS has the potential to be an Ethereum killer but who knows. These limitations are theoretical at this point since EOS hasn't launched yet, but the underlying technology of EOS seems sound to me. Others can fill you in here. But Ethereum can make a comeback. It's just unlikely for it to adopt large changes to the platform at this point since it already has many users and #2 market cap. Any changes Ethereum wants to make at this point has a lot of weight and a lot of consideration needs to be made. EOS can make any changes on the fly since it hasn't launched yet. This is why it's so important for EOS to continue development for a year, even though it could be launched now.

4. Then is it good idea to invest in EOS?

   • Depends how much you trust them, in the terms, this current token on the Ethereum blockchain states: "EOS Tokens do not have any rights, uses, purpose, attributes, functionalities or features, express or implied. Although EOS Tokens may be tradable, they are not an investment, currency, security, commodity, a swap on a currency, security or commodity or any other kind of financial instrument."
     This may just be a technicality because they can't promise anything, but if these tokens CAN'T be traded for EOS tokens on the EOS Platform or have any value attached to the EOS Platform, then we might be screwed over. But otherwise, in my opinion yes, EOS is a good investment, maybe not the best, the potential for profit and ROI may not be astronomical like Ethereum was, but I believe EOS is still undervalued in the long-term. If EOS, after token distribution is done, ever becomes a tenth of what Ethereum is today, then if you bought in now, you would begin to profit. Personally I would either get in now for short-term investment because many people transferred large amounts of altcoins to BTC for the free BCC (Bitcoin Cash), and are likely to transfer back to altcoin after this, so I would expect altcoins to rise a bit in a few days (just my unprofessional speculation), or I would wait at least a few months since we might be on a decline and end of a bull run in the crypto space (again, speculation), but I wouldn't be surprised, especially with the 12-month distribution strategy, for EOS to drop further in value this year. Especially next year as EOS nears launch and people start questioning what this this token is worth since they claim in the terms that it has no value. On the other hand, even though EOS is competing with Ethereum, as an investor, I would consider investing in both Ethereum and EOS. If you believe in the application platform technology, it doesn't matter which one wins out, you'll profit because one will skyrocket.