Some Labyrinth Lord House Rules

I've not been gaming much of late, and my Call of Cthulhu campaign seems to have withered, hence the lack of updates. So I thought I'd instead share some ideas I had for a Labyrinth Lord game I was going to run, and still may one day if there's interest. Labyrinth Lord is more or less a clone of Basic/Expert Dungeons & Dragons, one of my preferred editions of the venerable game but even so, there are some bits I don't like so much, and these are my changes and additions.

• Armour Class is flipped, so AC0 represents no armour at all and AC14 is as armoured as you get, which makes much more sense to me. Essentially, this means that at first level, a character's to-hit target number will be 10+AC. I won't go as far as a 3.Xe unified mechanic, but I like high rolls to be better, and the old add/subtract AC/to-hit system hurt my brain; I think THAC0 may be the main reason behind me abandoning AD&D 2e for other systems.
• "Skills" are similarly amended to roll high, so an elf, for example, detects secret doors on a 5+ rather than a 1 or 2. Same probability, more sensible to my mind.
• The Big d30 is an idea I've stolen from Jeff Rients. Once per session, each player may roll a d30 instead of the normal die, whether it be a d6 to discover a secret door, or a d20 in combat, or a damage die for a weapon or spell. It must be declared beforehand, and is not a reroll, and it cannot be used to roll for statistics or hit points. It also only replaces one die, so if a player wished to use the d30 on a 2d6 roll, they would instead roll 1d6+1d30.
• Thief Skills are rolled on a d6 instead of a d100, mainly because I've never liked that d100 chart. I've converted the probabilities, which has led to a bit of fudging, but it's close enough. A thief can use The Big d30 for these rolls. As an aside, I subscribe to the school of thought which says that any character can attempt to pick a lock, or climb a wall, and so on, but only a thief can pick a lock without leaving signs of entry, or climb a sheer surface.
  
  
  
  
  

  Level	PL	FT	PP	MS	CL	H	L
  1	6+	6+	6+	6+	2+	6+	5+
  2	6+	6+	5+	5+	2+	6+	5+
  3	5+	6+	5+	5+	2+	6+	4+
  4	5+	6+	5+	5+	2+	5+	4+
  5	5+	5+	5+	5+	2+	5+	4+
  6	4+	4+	4+	4+	2+	5+	3+
  7	4+	4+	4+	4+	2+	4+	3+
  8	3+	3+	3+	3+	2+	4+	3+
  9	2+	3+	3+	3+	2+	3+	3+
  10+	2+	2+	2+	2+	2+	2+	2+

  
  
  
  
  PL is Pick Locks, FT is Find Traps, PP is Pick Pockets, MS is Move Silently, CL is Climb, H is Hide, L is Listen.

The latter is the change of which I'm most wary, since the probabilities have been changed; I don't think it breaks the game, although I do think it will change the way thieves work in play. Until I actually see it in action, I won't know for sure, so if anyone wants to use this (or any of the other bits) in their Labyrinth Lord or D&D games, and would like to let me know how it works out, I'd be grateful.