I use crabapples in pieces rather than pressing them. I only just last year devised an apple press, but I've been making crabapple cyser since 2006. I roughly chop them and cut out any icky bits, if you're using bought apples that shouldn't have "extra proteins" included, you can just cut them into chunks. Ideally you'd want to mash them (crabapples are really hard and would probably break my masher so sometimes I'll steam them just long enough to soften them, shouldn't be needed for eating apples), but I think after a week or two of hard fermentation most apples will disintegrate anyway even if they were only roughly cut. And I always use a fruit bag for mine.
The recipe book I follow for fruit wines (Terry Garey's The Joy of Home Winemaking) suggests 8 lb crushed or chopped apples and 2-1/4 lb honey per gallon. She recommends getting rid of the seeds but I never do for my crabapple cyser. A 5-gallon pail of apples smaller than golf balls, cored? Nope. Halved or quartered, ickies removed, that's all I've got patience for.
And on pressing your own fruit: I go through a WHOLE lot more than $6 worth of trouble per gallon of cider I make. But if you've got all these apples and don't want them to go to waste, I think it's worth the work Plus, the apple cider vinegar I made out of the pulp was amazing. Of course, now I'm wondering what crabapple cider vinegar would be like... next year...
My suggestion, however you do it, is to use pectinase (pectic enzyme). Apples contain a lot of pectin and it can sometimes cause wines and meads to stay hazy.
"The main ingredient needed is 'time' followed closely by 'patience'." - The Bishop 2013
"Good grief! If someone wanted to murder you, all they would have to do is ship you a 55 gallon barrel of honey and watch you document working yourself to death!" - Vance G