well, if i'm being honest with myself, since the skis will only really be for trips to jay peak and a week in utah with the pops, i'd probably be doing more trees than the big lines i want to be able to ski. so maaaybe i could still pull it off and get something bigger and stiffer later in my life.
this would largely be in impulse purchase (mad deal on proform + dreaming of having an ep ski for years), but if the 178s would kill it in tight trees like you say, perhaps i wouldn't quite be completely wasting my money.