In my opinion, with long tail you have to work in bulk (50 articles, does that mean you are targetting 50 keywords/pages?) I worked for an online shop that sold over 15 000 different products and we did it like this (about 8 people):
Every week, improve 30 most viewed pages:
improve descriptions, photos, keyword research, add cross selling, upselling, drop 1-2 product reviews, build 2-3 links.
Over 2-3 months, it paid off pretty well, but we were targetting our most viewed/easy keywords because doing it all was just a no no.
By definition, long tail means you are trying to rank for lots and lots of (usually non-competitive or long) keywords. Link blasting can also be a great solution as long as you do it reasonably and carefully, but anything manual will require a couple of employees or freelancers.