• Configurable spider web lifetime, damage, minimum/maximum range, and cooldown
• Blacklist/whitelist mobs that avoid creeper explosions (or maybe alternatively different modes, like hostiles only, passives only or all)
• [Nope] Grant digger zombie's ability to break blocks with x seconds (configurable) delay after spawning (honestly this is just a minor quality of life tweak, and it'd help a slight compatibility issue I have with the datapack spawn animations that make hostiles spawn underground and dig their way up, as of now it makes them dig into the floor half the time)
• Make digger zombie's stop digging if they can't reach their goal within like x blocks (configurable)
• [Use vanilla commands or mods like MobsPropertiesRandomness] Configurable launcher creeper's attack damage (personally I'd weaken the damage and increase the percentage of launcher creepers to correspond)
• [Not in the scope of the mod] Add an option to for the ability to pick up skeleton arrows (as a config, maybe even with a maximum limit per skeleton to prevent farming)
• Digger zombie block blacklist/whitelist, or alternatively a block hardness value range requirement (only dig easy to break blocks) e.g, to prevent them mining obsidian bare handed

Configurable launcher creeper's attack damage

What do you mean by that?

When they explode they deal more damage or less damage

Grant digger zombie's ability to break blocks with x seconds (configurable) delay after spawning

The AI has been changed, they should take 3 seconds to start mining now