Glad you like it. Don't worry about it being a "proper bike" - a proper bike is one that you'll ride, and will last - and giant make good bikes. You'd have been fine with the aluminium, really - the steel tubing on one of my bikes is only 0.4mm thick, if you made it into a pop can you could crush that, too - but if you're happier with the cro-mo that's fine too.
Personally I wouldn't worry about the scratch, but if you want you can touch it up with one of the little pots of paint you buy to do the same job on cars. Since it's black you'll have no problem matching the colour.