First part of your post is you inventing my life, because turns out i did play update by update, and then talking about bugs when this is not something i brought up nor is relevant to what we're talking about, so it can safely be ignored.I think you have a biased because you only played the finished product. Like fisty123 said during the development there was some issues people including me complained about. Part 1 still had a bug that was reported to the dev but never fixed. That bug was even carried over to the Saikey release. The reason I believe a lot more people are complaining now is because during Part 1 everyone was so amazed at Fujino's game that a lot of people did not bother complain. Now we are all used to Fujino's quality so it is easier to find faults.
As for the pace, I would say it stopped in the second half of the Part 1. Think about it comparing it to Part 2. What actually changed between when Asuna started taking care of Inoda and the Fireworks night? Her lust? Nothing we can see. I liked the sex scenes but everything that happened during that period could be removed and nothing would change. At least in Part 2 things are changing. Too slowly maybe but things are changing.
Part 1 is great but now there are more games to compare it with, I don't believe it was as great as people think. But it is just my opinion. If you disagree, explain your reasons for it.
Second part still doesn't adress my point, since this is YOUR opinion while I stated the fact that most people really liked the pace in part I.
Anyway.