I don't have starfury (my system doesn't meet the requirements) So I can't really compare the two but I'll try to give a summary of DO item/monster levelling
The main_itemclasses.txt and main_monsterclasses.txt files have the descriptions for all items and monsters. At the top of each of these files there are a number of lines that tell the game how items should change when they are of higher level. changing these lines will influence all items/monsters in the file. This part sounds simillar to what you describe for starfury, you can set a linear, and a value increase for each setting. there is no 'uses levels' field here, so this file might prove difficult to mod.
It seems you can use different files for each map in your module.
In addition to this each individual item in the file can have one or more requirements, like a strength of 12 for a heavy axe, which can be set to increase per level for each individual item (percentage or number).
There is also always a chance that an item has special magical abilities, the chance for this can be set to increase or decrease per level, and this chance can be set differently for each map or shop in the module.
The magical abilities themselves are described in the itemmodifiers.txt file for items or the monstermodifiers.txt file for monsters. This file shows some promise for a templatizer program
. it has a minimum and maximum level setting for each entry, and no built in levelling, just lots of entries like the SEIV files.
In addition to this there are spells, each spell can be set individually to increase or decrease when gaining levels. there are *a lot* of level dependent settings here. To make things complicated: Items and monsters can have spell abilities.
I probably missed some options/features here, but it should give you an idea.
A summary:
The DO item system seems to be designed to generate a truly huge amount of different items with random (but level dependent) characteristics and weird magical abilities, it is very different from SEIV where you have a only a small fixed amount of different items you can discover.