I started off with an MFT camera after a lot of research, and now I find myself in a position wanting to upgrade to a camera+lens with good autofocus response. I wish I knew earlier, that this was a factor in choosing a camera/system. Now before my next purchase I wanted to know what are the top features that people consider while upgrading their gear. Listing those from experience in a single place would be very useful. Now to rule out the subjective nature from the question, I am going to list down things that I have come across till now,

• Upgrading to full frame for more pixels and data basically
• Faster burst rates and buffer performance
• Faster and efficient autofocus
• Physical aspects weight, ease of holding
• Availability of more lenses for a specific purpose (eg sharp lenses at some particular focal length range of one's preference)
• last one would be fancy features like wi-fi and better video capturing etc.

Is this a comprehensive list or am I missing any major points still?