I am a very big fan of EQ. I have no idea what an interface in a program is and really could care less. What I wanted was something that I could use with my computer to design quilt tops and have the computer calculate how much of each fabric I would need to make my design. I wanted to play around with color options and settings before I invested my $$ in the fabric of my choice. If I was doing an applique I wanted to be able to print out the the pieces so I could make my own templates out of a sturdy material. I also wanted a quick way to play around with different known quilt block combinations to see how they "worked" together. I also wanted to do sampler quilts. EQ does all of that. I knew about foundation piecing but felt that printing out tons of paper foundation was not what I wanted to do. I feel that it uses way too much paper. But you can also do that with EQ. I really like that it will figure out how many of each size piece I need for each fabric.
Like others have mentioned, you need to be open to learning how to use EQ. I have Dear Jane, Block Base and a couple other add ons. I have not looked at the Dear Jame program in some time because I found it very confusing when I purchased it way back when I first started looking for a quilt design program. EQ has come a long way towards being user friendly since I first purchased Dear Jane and EQ5.
The only thing that I would like to see is an active forum (like this) where there would be a forum format for just quilt related software posting so that users of the program can talk about the designing of blocks and quilts with each other. To me, I find reading other posts is an additional way to learn how something is done.