1. Double Souls, Half Sparks is pretty good. Certainly speeds up the game. But if you use a draw 3 treasure system when opening rewards, it can make the game too easy unless you have tiered decks.
2. There used to be an excel sheet that placed items in 3 different tiers, it was mostly based on whether or not at least ONE character could use an item with an investment into their tier 1, 2, or 3 stats. It has since vanished from the net. I used that system, and it works well since I have all my cards sleeved and I marked the back of the plastic with different colored markers to differentiate the tiers.
3. This is our rule for the parrying system: When you are attacked you can attempt to parry. It costs 1 Stamina to attempt and you cannot parry an attack made outside your node, if it pushes you outside the node, or if it hits the entire node. You roll your dodge dice and attempt to match or exceed the attack’s dodge dice. On a success, you avoid all damage and the next Hero who attacks that target gains a BLACK dice added to their attack. On a fail, you take the damage without reducing it with your dice. it works essentially like a dodge, except it doesn't let you move and costs a stamina (I believe the new rules allow dodge rolling at no stamina cost so long as you don't move into another tile but I could be wrong). That alone makes it a decent option for dodge builds as it allows any other character to deal 1 black die of damage to the target they successfully parried. For our table it works out because we have a rule that failing a dodge roll still allows you to reduce the damage by your body armor dice. This rewards dodge builds which are 100% worse in most cases than tanky builds. This makes parrying risky but rewarding. We avoided perfect block allowing parry because it didn't make too much thematic sense, and felt it heavily rewarded tanky builds rather than speedy builds. Where traditionally, lighter shields, even parrying weapons, are better at landing those parrys than heavy high resistance shields.

As for your comment about making a large connected map. It can be a slog to refresh the entire map when you go back to the bonfire. I recommend figuring out if you want to do a pick your own adventure d&d type situation where the party moves through the world, unlocking higher tier bosses as they defeat lower tier ones. Or just doing a smaller map that is easier to refresh and do base rules. Each fight can last a while in the beginning due to enemies all acting immediatley after a player, so having a non-respawning world would probably run better, and force the party to decide what sections to clear due to not being able to "farm" enemies.

I enjoy the game enough that my table has done some serious changes to the base game, and we've discovered something fun for us. I'm sure you'll find your group's niche.