Arena…
I agree with the comments you received. The key is specificity.
You may also want to combine listing individual projects with grouping repetitive work together. For example, when I submitted my information long, long ago, I wrote something like this (this is the shortened version):
"(1) Project engineer responsible for designing a 600-ft long, double-barreled 96-inch-diameter inverted siphon with reinforced concrete inlet and outlet structures on the ####### Canal for ###### Irrigation District, CA. The inverted siphon was constructed with elliptically reinforced ASTM C-76 culvert pipe. The inlet structure includes stop-log guides for blocking off either siphon barrel.
"(2) Project engineer responsible for designing a 3.0-million-gallon ground-level welded steel water tank with 18-inch CML/C steel inlet/outlet pipeline for ######## Municipal Water District, CA. Currently serving as Resident Engineer during construction.
"(3) Project engineer responsible for designing eight reinforced concrete structures for expanding the City of #####, CA, Wastewater Treatment Plant, including a 200,000-gallon circular clarifier, headworks with two Archimedes screw pumps, oxidation ditch, etc. Assisted with design of site grading and plant piping.
"(4) Project engineer responsible for preparing schematic designs for water and reclaimed water system facilities required to serve new developments proposed in ######## Municipal Water District, CA. To date, I have completed 12 schematic designs for proposed developments ranging in size from 6 residential units on 3 acres to 1200 residential units plus commercial on 550 acres. I am currently working on 3 more similar studies. These studies require computer modeling of the District's water and reclaimed distribution systems, developing project-specific design criteria, sizing pipes and any required storage tanks, booster pumping stations, and/or pressure reducing stations, and writing a report for approval by the District's Board of Directors."
Note: the "Project engineer responsible for designing…" was suggested by my boss. If I was writing this today, I would probably just say "Designed…"
Now to your document--Here are a few specific suggestions:
You said, "I performed heat load calculations on numerous buildings." I suggest something like, "I performed heat load calculations on 27 buildings ranging in size from 30,000 sf/one story to 400,000 sf/five stories."
You said, "…design work for pipelines…" I suggest something like, "Designed water and natural gas distribution systems for seven office complexes ranging in size from three buildings (120,000 sf) on 7 acres to eight buildings (725,000 sf) on 32 acres."
When you talk about backflow prevention devices, I suggest giving size and flow rate ranges. The same goes for everything else you mention in your document. Describe sizes, capacities, etc.
I hope this helps.
==========
"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill