Here is my thoughts.
[ ] [CAPSTONE] Runic Inductor
In my opinion, the Runic Inductor is the best KISS alternative. All designs are going to produce some amount of dhar, and the leyline network is designed to "eat" dhar.
[ ] [RUNE] Carved
Going ultra cheap here to save money elsewhere, because the rune appears to me to be not that important to overall function. Have a mason carve it for whatever good it does, call it a day.
[ ] [STORAGE] Expensive Material
Here is where I'm going big and spending the money not being spent elsewhere. We pay for material so as to not tie up the time of rare magical personnel. We use expensive material to make sure it can show benefits during big magical surges. (Also this is very dwarven. Spend money rather than blood, or in this case time, whenever you can.)
[ ] [FOUNDATION] Grey Lord
This is genuinely a tough one. I would like so much to use the clockwork alternative, but we're dealing with largely human lands here. We just can't depend on some ruler in 50 years or 100 years making sure springs are wound and clockwork is set. So that leaves us with Grey Lord or Collegiate. The light college based one takes less time but has far fewer people who can do it.
[ ] [TRANSMISSION] Leyline
This fell into our laps. Let's use it.
So.... Let me put some fake numbers to this. These are my numbers, but I think they provide a useful way of looking at this.
Costs:
Negligible = 0
Low = 1
Medium = 2
High = 3
Difficulty
Trivial = 0
Simple = 1
Moderately Difficult = 2
Very Difficult = 3
Costs: 0 + 0 + 3 + 1 + 0 = 4
Difficulty = 1 + 0 + 0 + 2 + 1 = 4
So this would be a 4/4. Would people care to rate their preferred versions using the same scaling?