Porter and alkalinity issues

So here's the water:

Cleveland OH municipal, filtered

pH:7.6
Sodium 20
Potassium 2
Calcium 38
Magnesium 10
Total Hardness 137
Nitrate .2
Sulfate 10
Chloride 31
Carbonate <1
HCO3 105
Total Alkalinity CaCO3 86

And the recipe:

9# Maris Otter
2.25# Brown Malt
.85# Pale Chocolate
.85# C45
.5# Flaked Barley
.5# Midnight Wheat

Including the roasted grains in the mash triggered a low alkalinity warning, so in order to keep my mash pH in line, I added 2.5g baking soda, as well as .6g Calcium Chloride as per Bru'n Water. When I took a 10 min mash pH reading it was 5.55 when predicted to be 5.2. Sparge water was treated w/ phosphoric acid to pH 5.7, I also added 2g CaCl to the kettle for flavor. The raw wort tastes kind of lifeless, lacking sweetness and body. Any thoughts?

Also, what type of malt should brown malt be keyed in as?, I entered it as a base malt @ 65L, maybe that skewed my data?

Thanks

I should add: while I've been all grain brewing for several years, this is probably only my 3rd dark beer. I've never used baking soda in a mash before, so this is new ground for me.

It appears that you included an appropriate degree of alkalinity to keep the pH from falling too low. 5.55 is right around where I prefer most of my stouts and porters. But that is a big difference if you were targeting 5.2 with the baking soda. Given the inputs, I'm not sure how that recipe would have produced a pH much lower than about 5.1 without the baking soda and it appears that the baking soda may have increased the pH by about 0.3 units. That is pretty good. I think your assumption of the Brown malt as a base malt is as good as anything. Who's brown malt is it? I found smokiness in Crisp brown malt in the past.

The baking soda adds very little sodium and it should not taste salty. If anything, it will add to the perception of sweetness. I find its tough to gauge wort character to beer character, so I wouldn't worry too much about the wort perceptions. Let it ferment.

By the way, your water quality data doesn't balance very well. I'm assuming that you haven't multiplied the sulfate value by 3 to bring it to its true concentration.

Thank you for your reply! I transferred the Ward report figures straight from the data on my phone, so I neglected to do the multiplication, I'm sure it's correct on the spreadsheet. In the past, I've held back the roasted grains till sparge but I was looking for a little more dark grain presence. I'm using 007 as my yeast & will "dry bean" this one with some cracked espresso beans.

Fawcett is the maltster for the brown malt, btw.