1) Closing Up Inventory / Gold
Technically, characterising every item would not be that hard. You just need to (of course) manually decide what alignment a given magical item is (if any), and flag it accordingly so that it bans users of the OPPOSITE alignment (for eg, Ring of Gaxx is unusable by Good Characters). There's a component in my Misc Mods that does the exact Opposite,
ie it removes the Alignment restrictions (I've always found it odd that Good Items rarely have Alignment restrictions, whereas Evil items do....) Too much Effort I feel, for something that will probably not be well received by Players.
Your party members controlling stuff you buy though, that would be a problem. Closing up Inventory as well, I just don't quite see that happening unless you can put them in some kind of permastun mode or something. That would be too problematic though.
2) NPCs that do not let them leave you in Certain Places
I used to try and implement this with Kova and Kiyone, where if the one was dead and removed from party, the other would leave with the body. Currently in BTL they leave and that's it, but my original idea was that the surviving one would keep coming back to Harrass you with attacks. Still, its not meaningful because its fairly difficult to write a reasonable, non-cheating AI script, where a previously dismissed party member is of any reasonable threat to the party (at any given level). Not to mention doing so for ALL the different places they could be pissed to be dropped off, and besides why would a Player who has run with the
NPC for that long want to do a perma-loss of the
NPC? (bar Yoshimo...) Since the
NPC becomes an enemy when forcibly kicked in such a way.
3) Gold etc were not enough
Locking up a gold amount, that would indeed be problematic. A better and far simpler simulation is a "gold drain" or a "Mercenary fee" given to each
NPC, something like a Party Upkeep,
ie at the end of every day, they take for themselves an X amount of gold (X can vary for different NPCs if you like, and can also vary depending on what level the NPCs are) If your gold falls below a certain amount, you are forced to choose which party member to let go of. This can be adjusted for individual
NPC Quests, for eg. if you're helping Keldorn with the Unseeing Eye quest, he won't take any gold from you until its completed, OR unless you leave the Sewers / related areas. Its just an idea and an example. Troublesome to implement, even more unlikely to be installed by ANYONE who plays
BG2, but nonetheless it is very doable, reasonable and realistic. I for one wouldn't play it.
Off the side note, in BTL Kova and Kiyone stay with you as you repeatedly refuse to give them up for Offers of Gold (
ie instead of you giving them gold yourself, you are constantly offered chances to turn Kova in for your own gold benefit). This earns their loyalty in much later stages, unless of course you happen to re-align to evil, then they will leave you just after
SoA ends and Irenicus is killed in Hell. Late-stage BTL also gives you a chance to reward (
ie give gold) to a particular Bioware
NPC if he is in your party, who will otherwise betray you later on. Giving the right amount of gold is important - giving too little causes him to betray you later anyway.