Both 2E/F and 3E/F are suitable options for a couple on A380. I've done row 3 before with Mrs. QRC.

2A and 3A definitely are a bad choice given your line of questoning (they're great seats either as a single traveler or a couple who doesn't want to interact though...). As mentioned above, you seem perhaps a bit confused about the seat. There is no ottoman, and definitely no way for front back seats to interact save standing up on your seats or going outside the suite into the aisle.

Note the middle seats cannot dine together given the design. Hard to share food. But the two middle suites are really nice as a couple because you can close the outside doors, open the middle divider thing and it feels both intimate and spacious. The middle seats are obviously the right choice if you're desiring to do a lot of interacting with one another.