I am building an Exhibit (see the Guide for Authors) for a personal project. I have a 1300 line spreadsheet that I decided to make more user friendly by putting it up on Google Spreadsheets and creating a more-easily searched, sorted and filtered view of it via a webpage.
Building the Exhibit itself was simple - uploading the xls and tweaking headers and formats, creating the json feed, building the views. What I'm spending the most time on is data cleansing - four-fold more time manipulating the data over publishing it. It's not that the data is bad to begin with - it's quite good, actually. I've found but a handful of word choice errors (as opposed to spelling errors) as I've gone through the sheet. All of the information required for this project is there. No one would ever complain about the quality of the data in its original format, in fact, its authors are to be commended for the hard work they've put into it.
What I'm having to tweak is the model itself. I am going line by line modifying the primary label where needed, simply so the rest of the information is clustered and displayed in Exhibit in a reasonable way - less confusing to the reader and to my personal standards. Should I lower my standards? I could. But I can't. The hours that I spend tweaking this file will make a world of difference for my audience. In fact, I am sub-optimizing my tweaks to get it done quickly. If I do this project again next year, I will do some things a bit differently and allow myself more time before the event to do it better. My audience is happy, but there's always more that can be done to delight them. One step at a time!
Keep this in mind as you embark on migration and integration projects. What looks great on its own may require additional work after it's modified in some way. Plan for it to avoid frustration and critical response from your audience. Do no harm! If what you deliver isn't better than what they already have, you've failed. Be agile and deliver often, if that's your strategy, but be sure it's quick and the messaging is on target. Be open about the next steps. Your users will appreciate the transparency.
Needlebase or Refine
If you're doing this in a spreadsheet, it's taking you way longer than it should. Either Needlebase or Refine would, I bet, allow you to do *super*-optimized tweaks in less time than you're doing sub-optimized ones "line by line".
[PS: shame on your comment system for pedantically insisting that I manually type the "http://" at the beginning of a "Homepage" field.]