Thanks for the great suggestions, Evan.
Unfortunately, this doesn’t fit our feature request guidelines. Each thread must be for one single feature and this is a collection of many features (more on this here). For this reason, I’ve set it to auto-close in a couple of weeks. That should give us time to have some productive discussion first, as there is a lot of really useful information in here. When it closes, anyone who has voted for it in the meantime will get their vote back to use elsewhere. What we need is the votes to sit with the individual feature requests, rather than the more general “Enhanced production features”.
Despite what I’ve said above, thank you for bringing these points up, it is very useful information 
and will help us make Breww even better, even if it can’t sit open for picking up votes 
I’ll cover each of your points below:
Define the data management process (required measurements, calculations, etc.) separately from the recipe.
I think this would be covered by Reusable/shared recipe stages (when edited the changes apply to all recipes using them). Do you agree?
Define recipes in ratios (percentages for malts, lbs/bbl for hops) so that they scale to different brewing systems or batch sizes
Breww already has full support for scaling, so I don’t think this is needed. It works slightly differently from how you suggest. You define a batch size on the recipe and enter all ingredients as if you were brewing a batch of this size. Then when you make an actual batch, if you enter a different batch size, Breww will scale the ingredients accordingly (assuming you have this option checked when starting the batch). More on how this works in our help guide: How does Breww scale the ingredients on batches (and how does this change with multi-turn batches)?
More robust scaling tools that scale malt based on mash efficiency, batch size, and losses, and hops based on IBU target, batch size, and losses
Some of this already exists, such as adjusting hop quantity for alpha acids, and of course batch size (as above). And I think the rest would be covered by a combination of:
- Calculations on brew sheets with ingredients specifications
- Recipe-level variables for Calculated Fields, e.g. allow "Add ingredient" quantity to be the result of a calculation
Please comment on those threads if you feel more is context is needed or if you think an extra feature request is required, please open one for the specific request.
Start with the recipe, scale to the system/batch size/number of turns for ordering ingredients/building bill of materials, plug in lot attributes and adjust quantities for brewing.
I might be wrong, but I think this is all covered by the above existing features and feature requests. Please do let me know if you disagree.
Allow custom functions that can be reused across calculated fields
How does this differ from our existing Calculated fields feature? Especially when it has the extras of the recipe-level variables feature request mentioned above? Again, if you think more is needed here that’s not covered, please do comment on related existing requests or open new requests for the specific features that you’re looking for.
Include common brewing functions (see MBAA Handbook of Basic Brewing Calculations)
We’re soon expecting to work on exactly this, as part of “production focus” that we’re working on. That production focus also includes some of the above-mentioned feature requests, so a lot is coming to this area of Breww soon
I’ve ordered us a copy of that book, thank you for the recommendation! And, thanks for sharing your existing recipe template, that’s also useful for us to see when planning and working through some of the features in our production focus. Thank you
Thanks again for raising this. There’s a lot of helpful information in here.