[I am transitioning to mediums...]
I would focus on making the established deep frames as a basis of the hive for this year.
Your bees have pollen stores and cured honey in desirable locations.
If you start to change these frames now, it will be a significant stress on the hive.
I would save any change to mediums until next year - I'll explain why in a minute.
I would take the time to try to get them to draw and put stores in mediums this year.
This way you have drawn combs that are empty for the spring.
In the spring I would rotate the medium bodies in and allow the bees to put the appropriate stores in the appropriate empty cell locations for next years development.
You may need to use an excluder to keep the queen out of the deep that you are replacing.
Your bees may try to put up stores in the deep until all brood is emerged.
Plan to need to extract the deep frames next year.
If you try to impliment the above this year, you bees may not structure themselves for the best winter survival. I'd rather wait and have alive bees next year than force something that results in a dead-out with medium frames.
[Maybe I was expecting too much (like 2 full brood boxes) from a first year package in a year that was a month behind schedual weatherwise. ]
This is not an unreal goal. Your bees were storing your syrup. The question is where in the hive and why? If it was in the brood nest - did you have full frame of nectar that acted as a wall preventing the bees from expanding onto other frames? If so, you now know that you have to move those frames to the walls of the hive body. If it was above the brood area, the syrup was wet and the bees attempted to cure it. Either thicken the syrup, add more frames to spread out the nectar, or extract to provide space.
[What other tips do you experienced beeks have on feeding or managing a first year hive for those of us stumbling along.]
Hint 1:
Bees like to move up and down more than they like to move sideways.
To get quicker results in drawing and brood frames be sure there is room above the brood nest.
Many colonies will establish faster as a two story 5-frame colony than a single 10 frame box.
Consider dividing hive bodies in half. Once most of the frames are in use, expand to full hive boxes.
Hint 2:
Keep the brood nest warm by keeping several brood frames together.
Don't try to expand by splitting a brood nest too thin to where the brood chills.
Dead brood is a huge set back that takes a hive a long time to recover.
Hint 3:
Queens lay based upon pheromones that reflect congestion.
Adding frames and keeping feed source away from the brood nest improves queen laying.
Open feeding away from the hive can be tricky because it can cause robbing, but it can be done carefully.
Otherwise a slow top feeding is good.
Higher egg laying will result in more brood, more bees, and a better yield (or establishment).
[I didn't know that beekeeping was going to be so close to my master's thesis in Biology!!! ]
Nice thing about beekeeping hives is plagiarism is not only allowed, but encouraged!
Looking at your neighbors answers (adjacent hives) does help!
Keep in mind your paper is a recently conceived theory, bees are an absolute proven by millions of years of survival.
-Jeff