did you mean 70 pages or 700? If it was literally 700 pieces of informtaion that might be a good indication of the reason for delay. 700 pages of documents is astounding and to be a little frank, overkill. The consulate officers are looking for consice information that is clearly spelled out for them. Imagine if everyone brought in 700 or even 500 pages of documents when the officers is looking for specific information. It would be an insurmountable task for them to undertake. Think of it like this, you have to spell out what they are looking for in easily digestable formats. If they are asking for a letter from the petitioner about how you met, make it into bullet points of the most important information that would generally fit on one page. If they want who paid for the tickets a reciept or screen shot of a credit card statement, paypal transaction, wester union transfer etc. Family tree documents can be bullet pointed in the same way as the petitioner letter. The point is you should resist the urge to show all of everything that you have available to prove your evidence. Most of it should be quite self explanatory.
As for the other part of your post the Tax returns, stocks, bonds, financial information etc. and the affidavit of support I too sent 3 years worth of tax transcripts, bank statements for a year (the summary page), savings information, yadda yadda. The consulate officer didn't even look at them or take them or make copies. While the petitioner is required to have and be able to prove they make 125% above poverty level all of that information will generally be "proven" when you go to adjust the status. That's where it really counts. If the consulate officer looked over the financial information and didn't take any of it then they didn't want it. They are the ultimate arbiters of our fates (unfortunately). Perhaps they looked and were satisfied with what they saw.
Lastly to address the overall "time to make a decision" part of your post. My fiance and I went through the same thing at the London Embassy. The long wait. We could do nothing but check the CEAC daily (sometimes several times a day). Ours finally changed to Refused, then Ready. We were horror struck and downtrodden until a quick google search showed that this meant his visa was going to the IV unit and within a few days it changed to Adminstrative Processing then Issued. Our total wait from the last piece of 221g information being submitted to Issued in CEAC was about a week. Keep in mind though this was after a December interview where he had to get a new police certificate (that took about a month) and a new medical (another month), then some follow up paper work to the visa medical group before they would send his medical to the embassy. All said from the interview to issue that was about 2.5 months. YMMV.
A 221g is far from an outright denial. It means they are constantly looking at your case so they can wrap it up one way or the other. A search on this site will show you that often times the 221g is the means to an end for a very long and anxious wait and an Issue notice from the Embassy. I wish you the best of luck, I can tell you in my case, it was so SO worth the sadness, uncertainty, tears and all the waiting. Cheers