They're very strict about dimensions so as long as your soft bags are within their range you'll be fine. Remember any handbags count so if your good lady wants one that counts. What my wife does is stick her hand bag inside the case and then retrieve once you're on the plane.
I wouldn't worry too much about the weight you're carrying on. The allowance is 10Kg. For the dimension of case you're allowed that's generous.... unless you're carrying gold ingots
As part of the online boarding process, you have to enter your passport numbers and name - EXACTLY as it is on the passport.
You can print your boarding cards off up to 15 days in advance so you should be able to print off both outbound and inbound boarding cards if it's a standard length holiday.