Awarded conversion rate optimization (CRO) expert. Google Analytics certified. Google Adwords Partner. 8+ years of experience, 70+ clients from various industries
As a rule of thumb, I would still begin from the wider part of the funnel.
if you have a lot of traffic and with that probably a lot of different traffic sources, campaigns, marketing efforts, expectations of the people coming are likely different. Optimization in that case should be done for certain traffic source or visitors segment only. If you manage to get more of those visitors to go down the funnel, you'll get more "juice" to play with and test in the next phase: optimize the next step in the funnel for those visitors/segments only. This would be done much harder (read: slower) if you began from the bottom up.
If you could give an example of the old vs. the new link the answer could be more precise.
But in general, the first thing I would do would be to make a redirect rule: either in htaccess file or on server-side you need to tell that all of the old links now should lead to the new pages' URLs. This is done through 301 redirect (permanent redirect) which would mean that all of the old links would pass the link juice to the new ones and the search engine would re-map to the new ones after some time (depending on the tempo of crawling your website).
I would leave those redirect rules active for quite some time though: old backlinks would still be leading to the old URLs. If you see in your analytics service that you get a lot of traffic juice from one or more sources specifically, the best idea is to get in touch with the webmaster of that site and ask for old link to be replaced with the newer one.
You might want to try Clickwebinar for webinars. I have used their service seamlessly for a couple of months on MacOS and they do the recordings.
They are not good though if you need to constantly interact with the audience because the delay in speech through their server is too high (or at least was too much for my standards). In those situations, I presume Skype's or Google Hangouts screen sharing feature is just about enough.
If you need to record the screen even when using Skype or such, try SnagIt (http://www.techsmith.com/snagit.html)
Hope you'll find this useful.
You actually can't do it because limit of ad groups per campaign is 20k. But in general, I also practice this approach with up to 10 keywords per ad group and for the successful ones even one keyword per ad group.
One of the pros are more focused ads for each of the keywords, providing better targeting. Cons are of course headache with managing that much ad groups and problems with quality rank within a campaign. And yes, of course you would need to set negatives for each of them against all the other ones.
Bids and budget are not a universal rule; they depend on the industry, targeted country, etc.
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