Love it,  I'm a rabid fan of David Deutsch and think he's essentially answered these questions, so for fun I'm going to take a stab at them below.

• The definition of “progress”: Increase in wealth, which is "the set of possible transformations." This occurs through knowledge growth, which was described by Karl Popper as a process of conjecture and refutation.
• How to measure progress: Again, how do we measure the number of possible transformations? When the Wright brothers discovered flight, they opened a new set of possible transformations. (I wonder - what's the value of measuring this?)
• The value of progress: pro, cons, risks, tradeoffs - Stagnation means extinction, this is not a viable option. The cons are all the problems that new discoveries potentiate. The trade-off is that we can't solve old problems without creating new problems. In fact, new problems are one way to measure progress. 
• The causes of progress, and which ones are fundamental: Knowledge growth is fundamental.
• The intellectual history of the idea of progress: The history of the enlightenment? Of mini-enlightenments (ie Athens).
• Technological stagnation, and its causes and solutions: Anything that prohibits conjecture and/or criticism causes stagnation. A culture of criticism and open-ended brainstorming can't help but make progress.
• Histories of progress in various fields (as are often featured on this blog)
• Opportunities and bottlenecks in various fields: What processes interrupted conjecture/criticism in those particular fields?
• Visions of the future: A dynamic society, dominated by rational memes where anti-rational memes (memes that survive by disabling criticism) have no purchase.
• Progress and safety (including existential risk): Knowledge growth, problem-solving and wealth creation.
• Progress-minded approaches to other issues of the day (climate change, poverty/inequality, war, etc.)
• The philosophy of progress in comparison with other approaches, such as Effective Altruism: EA is too focused on cause prioritization, which necessarily involves prophesy. Just focus on the interesting problems and let 'er rip! EA would do the best if they simply highlighted problems they find interesting for reasons of neglectedness, scale, impact on wellbeing, etc.
• Research funding (including current efforts in alternative funding models)
• Progress in science generally: All the same - conjecture and criticism. Identifying the enemies of each and improving.
• Progress in morality, government, and society: Same as above.