Hi there and welcome!!
Given the amount of coffees you will be making, the Silvia will be a very suitable coffee machine for you. It makes excellent quality espresso for minimum capacity requirements. Youd be pretty happy with the silvia/sunbeam combo. You are right in saying the grinder is more important, however, dont forget that you also need FRESH COFFEE!! ;) Make sure, when you buy coffee, look for coffee bags with a one way valve to let the carbon dioxide to escape but keep the oxygen out - not to be underestimated!!
Good luck with your searching, feel free to contact us if youd like any advice. :)