Some of these tips are questionable! In week 60+, I still haven't upgraded it, unlike the number of hero slots. There were very few situations where this made a difference. And with weeks where a whole bunch of heroes arrive, it becomes very easy to recruit the necessary ones. Moreover, the carriage costs MERIT (or whatever they're called in the "orthodox" version?), which is better spent on upgrading the forge.
And I would also argue with some of the other points.