1) Merged mining: Is it really the same like mining Litecoin and Umbrella LTC with full hash rate separately? Why is not everybode merge mining if that's the case?

2) I might consider myself as Crypto-Newbie and have talked a lot with "non-tech" people about Cryptocurrencies. They don't get the revolutionary point and they don't care about the fascinating technology behind. All they ask is, why they should use them instead of credit cards etc. and where they can pay.

I think Umbrella coins could be the bridge to mainstream adoption! Think of PayPal - I really disregard them as seller, but from a buyer's perspective they are great. They offer security - or at least the feeling of security. This makes them successful despite enormous fees for the seller. If you can setup a similiar payment processor which is easy to use, has low fees, fairer dispute resolution and the backup of "umbrella insurance" it may be a huge success. I love the idea of secure exchanges. Also easy usability - I had smartphones long before the iPhone came out and nobody understood my need or fascination for them - think how Apple changed the market after that.

Cryptonerds might not like this kind of "institutional backup", but people generally trust institutions more then technical elegant "trustless" solutions - so yes, go for it - build the bridge for mainstream adoption