I love OSR D&D because of its simplicity and efficiency. It’s definitely my game of choice. The one thing that I don’t like about it is that it takes forever to level up and then the payoff is really small–a few more hit points at level 2 and a spell if you are a spell caster. Saves and attacking don’t increase until level 4 at the earliest and thieve’s progression is disheartening.
To address this with my group of newbie adventurers, I brought in some modified feats from the 5e SRD. When the characters reached level 2, they each got to choose a feat and can then choose a new feat every other level thereafter. I broke the feats up into “general” and class specific sections and it has worked out nicely.
They do not overpower the characters and actually help a lot with defining the character roles within the group. Most of the feats are far less powerful than merely hiring a mercenary, purchasing a war dog, or finding a magic item. In fact, all of the feats taken by the group combined have had less of an impact on encounters than our Cleric using a potion of animal control and his speak with animals spell to bind a pair of panthers to the party.
The players love the feats, as it gives them a chance to customize their characters and makes leveling up a lot more fun and something to look forward to. Now, when someone levels up, the whole group is engaged, as they discuss the pros and cons of various feats and how each one would fit into the overall party. For a group of beginner players, this is a great system, because they don’t completely understand all of that at the beginning of the game when they are rolling up their characters. The feats give them a chance to customize and maximize their group roles as the game teaches them what they need and, in turns, means that I have to rely less on NPCs to fill the gaps.
My next step will be to add the option of choosing a cantrip instead of a feat if the character is a Cleric, Magic-User, or Elf. We’ll see how that goes.