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Create one crazy, amazing, awesome interactive infographic that nobody but a developer could implement. Create an MVP version of it within your 20 hours and then ship it. If it gets great traction or response, build upon it. Distilled has done some awesome examples with their client SimplyBusiness. Here's their case study list https://www.distilled.net/services/. Here's an example of one that did well -  The Small Business Guide to Twitter but there are other great examples on that page.

Yes, you should create shorter excerpts. There should also be an option on WordPress to allow more than one blog post on the home page, you should increase this number, so each page is differentiated better than the home page and blog post.