I'm a psych major, and my experiences with the department have been fantastic. It's not the largest department here on campus but it's also not the smallest - I have found the size to be just right. Intro to Psych classes will be decent in size (about 40 students per class), but as soon as you get that one out of the way, just about all the psych electives have no more than 20 students (I have found 12-16 to be the average), and the classes allow for some great discussion and cool hands-on opportunities. Most of my favorite classes that I have taken during my time at Bowdoin have been within the psych department. There's also quite a bit of opportunities for research with professors, especially during junior/senior year. (A lot of students choose to do independent studies and/or honors projects). Feel free to PM me if you have any questions specific to the requirements for the psych major, professors, curriculum, etc. Oh, and the psych department recently (about 3 yrs ago) got a nice new building (Kanbar Hall), so the classroom and lab facilities are fantastic.
I'm not as familiar with the English department (I haven't taken any classes within it), but I have heard good things. As stated on the website, it's the fourth most popular major, and from what I've heard, there are some pretty awesome professors within the department.
As for double majors, I feel like there are LOTS of them (myself included). It's definitely feasible (I'm actually doing a minor as well - so it's definitely do-able if that's how you decide to divide up your schedule).
Hope this helps (at least a little...)!