I’d never heard of the conversational queries and LSI so thanks for adding to my SEO awareness of new trends. I would add a few more things which seem to be becoming more pertinent in 2015 such as:
- Proportion and relevance of anchor text in backlinking: running backlink reports regularly are a good way to see the seo activity on your site from the “algorithm”'s eyes. having many non-relevant anchor text links can confuse Google in understanding what your site is about
- Trust flow is more important than volume of backlinks: it’s better to have a handful of excellent quality/high trust flow sites than 3000 links with low trust flow and irrelevant association to your industry
Remember that Google is an algorithm so every SEO action you take must somehow be readable by Google to indicate that your site is trustworthy and reputable.