Thanks for starting to tackle this issue a bit (even though those needing the fix the hardest aka beginners won't get it. Hence a fast official patch of that issue at least is in order...)
For me the refusal of money-demands does indeed stack (sometimes with a delay which might mislead. Am not sure about that one. Im at -5 currently for dead sure.). Is my version buggy or is yours Dale? Or did you just got a wrong impression from the delay... Not that it hurts in any way though...
King can bite dust...
But besides a quick fix, other factors besides Liberty-Bells (as only source) should really play a role in determining the size of the ref (and the Bells in turn should effect the whole thing less) to make it more interesting and seem more organic (and to balance the game out better and make it less exploitable...)
Possibilities / necessities in my book are:
Instead of a flat value for each increase in the ref, make:
Progressively raise the treshold of bells needed for each! Ref increase for each! unit that gets added to the ref. Raise it for example by 10% (like the way education advances progressively) multiplied by the handicap modifier. That leads to a hard cap to Ref from bells quite fast if you go all out bell-mad. Especially in lower handicap levels (preventing at least pilgrim and explorer-level players from getting swarmed.).
So if the 10% example is taken, each ref-unit at conquistador level roughly does come at 75 Bells for the first unit, rougly 82 for the next / second unit, about 90 for the next / 3rd unit.
At pilgrim it whould be more like 75 Bells for the first Unit, 90 for the second, 108 for the third and so on and so forth.
For revolutionary it whould rather "just" be like: 75 for the first, roughly 78 for the second, 83 for the third and so on and so forth...
You get the picture.
Please don't all shoot on the number used, its possible to use it / change it until it fits. (5% or even as low as 2% might! be much more reasonable. 10% is just easier to understand and calculate such an example imo.
)
Now one could argue that the bonus to WoI battles and founding-fathers are such a huge deal as pretended by the game. But honestly they aren't in comparison to what you get if you exploit the ref=bells Equation. Id rather fight the King with 3:1 odds staked for me than 1:10 odds staked against me. No matter how hot founding fathers are (supposed to be...) and how powerful the whole sentiment-bonus to colonial forces during WoI is (again: supposed to be...).
(Remember that time is a big factor in winning as well. So the 3:1 odds for me with weaker troops is doubly effective.)
What you suggested / implemented here sure makes sense and gives a strategic choice of what to focus on.
To smother the effect of the cap a bit and take into account other sources of resistance / power to fight back also let the following things have an influence on the size of the ref (which also helps to fix some serious exploits.):
the number of maximum! colonists in a colonial powers control during a given game should effect the ref (should have medium influence perhaps to about half the degree that bells do in an averagely played game without metagaming. Thats to prevent the unthematic mass-disband of colonists pre bomb-shelling sentiment in the small leftover colonies in no time...
Number of colonists gained / bought + converted overall is a very bad base [even if it whould be by far easier to track i recon] because of some cycling going on during the game and other issues. But i have no idea if its easy to track the overall maximum of colonists a colonial power did posess in a given game.)
the number of cannons should effect the ref (to a small to medium ammount. Bought ones should effect more like about twice as much than manufactured ones.)
The number of guns bought effect the ref (to a smaller ammount really. Manufactured ones maybe should be exempt. Because its rather hard to produce (hardest good to produce in the game if im not mistaken?) but those things are really easy and rather cheap to buy in Civ4:Col. At least in my experience and in comparison to col 1.)
Overall Gold gained (should only effect the whole thing in a small way. But here gold gained seems ok since fluctuation on a big scale is rather normal and you get a lot from trading alot. Perhaps just Gold traded with / from Europe will suffice. It might lead to some awkward results but if the influence is not all that overwhelming it whould lead to a small variation between games. Which might be a good thing if it makes it harder to downright calculate the ref in a feasible way for even hardcore math-geeks.)
Number of surplus food available at max (including sitting in ships and Wagons, 300 Food are a colonist after all) at a given point if trackable (should only have very minor impact but its a cheesy cheat to fastgrow after disbanding all your population. That last one seems minor in comparison though and hard to track. So if its to much hassle perhaps just leave it out.)
And all! those Ref modifications should directly also scale to handicap level + possibly have a quasi-cap by progression at least for the lowest 2 difficulties. And of course the ammount generated by those should lead to the Bells part / influence beeing reduced accordingly. Because the Ref will still grow big enough. But less extreme and less exploitable (no more 5:1 or 10:1 stakes possible vs. the King... and no 10:1 for the King on Pilgrim either...)
With the bell part still playing a big role. But not a huge one and certainly not the only one... (whould be easily modified by changeing the bell-treshold progression until the whole thing fits as is liked.)
Try to add those thoughts to your quick fix if possible in a reasonable timeframe and have a look (+ let others look into as well) how the whole thing works out.
. An interesting way to achieve independence.
