Failed to call hook 'OnServerCommand' on plugin 'Logger v2.2.1' (FormatException: Index (zero based) must be greater than or equal to zero and less than the size of the argument list.)
  at System.Text.StringBuilder.AppendFormatHelper (System.IFormatProvider provider, System.String format, System.ParamsArray args) [0x000ff] in <ac823e2bb42b41bda67924a45a0173c3>:0 
  at System.String.FormatHelper (System.IFormatProvider provider, System.String format, System.ParamsArray args) [0x00023] in <ac823e2bb42b41bda67924a45a0173c3>:0 
  at System.String.Format (System.String format, System.Object[] args) [0x00020] in <ac823e2bb42b41bda67924a45a0173c3>:0 
  at Oxide.Plugins.Logger.Lang (System.String key, System.String id, System.Object[] args) [0x0000e] in <794996da97b54ea2b5d8fb735211fcde>:0 
  at Oxide.Plugins.Logger.Log (System.String filename, System.String key, System.Object[] args) [0x00031] in <794996da97b54ea2b5d8fb735211fcde>:0 
  at Oxide.Plugins.Logger.OnServerCommand (ConsoleSystem+Arg arg) [0x000f8] in <794996da97b54ea2b5d8fb735211fcde>:0 
  at Oxide.Plugins.Logger.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x004cb] in <794996da97b54ea2b5d8fb735211fcde>:0 
  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <9affce1cd15c4ec183941adef8db1722>:0 
  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <4452f821def6406d834e4149849fe7ea>:0 
  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <4452f821def6406d834e4149849fe7ea>:0

Got this on the plugin freshly installed and lightly configured with a couple of blacklisted commands (all json is fine)
Seems like there is a bug with the OnServerCommand check?

Would love to get tips or ideas

Looks like an issue with your local oxide/lang file for the plugin.

{
  "CommandReason": "reason",
  "CraftingCancelled": "{0} ({1}) cancelled crafting {2} {3}",
  "CraftingFinished": "{0} ({1}) finished crafting {2} {3}",
  "CraftingStarted": "{0} ({1}) started crafting {2} {3}",
  "ItemDropped": "{0} ({1}) dropped {2} {3}",
  "NotAllowed": "You are not allowed to use the '{0}' command",
  "PlayerCommand": "{0} ({1}) ran command: {1} {2}",
  "PlayerConnected": "{0} ({1}) connected from {2}",
  "PlayerDisconnected": "{0} ({1}) disconnected",
  "PlayerMessage": "{0} ({1}) said: {2}",
  "PlayerRespawned": "{0} ({1}) respawned at {2}",
  "RconCommand": "{0} ran command: {1} {2}",
  "ServerCommand": "SERVER ran command: {0} {1}"
}

Tried playing around with {0} {1} {2} at "ServerCommand" but to no luck