I make quite a few Czech Pilsners and Munich Helles batches and I use 100% Lake Michigan water. I use lactic acid in the mash water to lower the pH (I add it to the water as it's heating) and also to neutralize the bicarbonate and then I would add anywhere from 2-3 grams of calcium chloride to that to boost the calcium. The SO4 in the source water is 27 (9x3 as SO4-S) which is slightly high for something delicate and I will occasionally use 25% distilled water but it's not really necessary. I consider Helles to be one of the more finesse beers you can make and I have made some dynamite batches of helles with 100% source water. I will also say that when others suggested using some amount of distilled or RO water, those batches came out nicely as well but I was really looking for a way to stop lugging water around... especially if it wasn't necessary.
Your process is solid, I've done it that way too. In fact I'm sure I've read some of your posts on other boards and learned a few things. And from one gelatin-finer to the next, if those beers taste anywhere near as good as they look in your pics then dynamite indeed!
Homebrewing can be funny sometimes. I use 100% RO in large part for the opposite reasons that you mention. I don't mind lugging the water around - I keep the jugs in my trunk and fill them whenever I'm at Mariano's. I was, however, looking for a way to stop messing with the water spreadsheets and tinkering with mash pH. Certainly nothing wrong with those, but I just wanted an extremely simple, consistent and streamlined process on brewday.
The ah-ha moment for me was over the summer when I read through Gordon's new book. I went all in on his approach to water and haven't looked back. But who knows, maybe that will change again...
Cheers and again, welcome! Beerhead.