Post: #2

1) you can check all AI flags on sphere.ini, NPCAI flag 04 is NPC_AI_EXTRA, which is used to enable some extra AI actions like: try to find/equip weapons/shields on combat or light up torches at night

2) shields are used mostly to parry attacks, not to increase AR/resist. So using shields you won't get too much AR increased but on the other hand you will parry (block) more attacks, which is the same of resist 100% of the damage

3) probably this is a network issue, because sphere can handle a lot of clients at the same time, but bad things will happen if you try to host it on an small AWS cloud with slow network. Some cloud/VPS hosting have connection limits on plans, usually cheap plans have cheap performance and only allow 50~100 connections. So try check your hosting limits, or you test an upgrade on your plan to check if it will fix this problem