My quick answers:
1) Get a platform that can make great espresso. There are a wide range of machines/grinders that cover that over a wide price range. I think if you went elchepo and reach the limits of the machine quickly you will be disappointed.
2) Yes without a doubt, but Silvia can be a finiky machine and will require some persistence. She and Rocky can deliver superb espresso. See 4
3) Depends on whether your dad wants an espresso machine. Sounds like you are spending his money for him here ;)
4) Will your dad be operating it? If so do you need a machine that your dad will find easy to use or is he likely to search for espresso Nirvana as well? Im going out on a limb here but the EM6910 would also be worth a thought as it may not have as steep a learning curve.