posted on Steam; re-posting here for visibility
Doing a little digging on other uses for glass making in Medieval Times, I discovered ‘Forest Glass’ and our villagers need it! 
Forest Glass is used to make green tinted Drinking Vessels and is made from sand and pot ash, which is derived from wood ash.
The addition of Forest Glass would give us another glass-type production option and item type in the Glassmaker; Tier 3+
A New Production Building would be needed to produce Wood Ash that would be used by the Glassmaker when producing Forest Glass.
A New Production Building would be needed to produce Pot Ash that would be used by the Glassmaker when producing Forest Glass.
OR just a single New Production building that makes Both Wood Ash and a different production within it could convert Wood Ash to Pot Ash.
** Forest Glass Drinking Vessels were used in Medieval Times for drinking Ale, Wine and Mead **
With the addition of Forest Glass, we would also need New Production Buildings: Winery and Meadery with Ale being a new (second option) in the Brewery.
Of course, we would also then need New Crops (we already have Apiaries/Honey for the Meade), Grapes: Pinot Gris, Riesling, Cabernet Sauvignon, Merlot.
*All new beverages could be purchased at the Pub? Unless we could also get an Alehouse, a Tavern or an Inn.
*The Inn could also be used to temporarily house Immigrants when players weren’t prepared for the sudden Boost in Population.
In Summary:
New Raw Materials Production Buildings:
• Wood Ash
• Pot Ash
New Produced Items Production Buildings:
• Ale (produced in the already existing Brewery)
• Winery
• Meadery
New Crops:
• Pinot Gris Grape
• Riesling Grape
• Cabernet Sauvignon Grape
• Merlot Grape
New Buildings:
• Alehouse
• Tavern
• Inn
New Usable Items:
Forest Glass Drinking Vessels
*Whew! I think I got it all!
Just my .02 