By the RAW, characters in Savage Worlds earn 1-3 experience points per session, although in practice it usually works out at 2-3 for most groups - and as 5 experience points grant an Advance, some GMs find it easier to simply award everyone half an Advance per session. This means that PCs can improve something every two sessions.
Some GMs dislike characters advancing every two sessions, and instead prefer to double the number of experience points earned, so that PCs gain one Advance every session. The obvious drawback of awarding double experience points is that the PCs advance at twice the recommended speed, and can rapidly outpace the challenges in a campaign designed for characters using the normal advancement rules.
One Advance can be used to raise an attribute, buy an Edge, buy a new skill at d4, raise a skill above its linked attribute, or raise two skills below their linked attribute. But if PCs can raise two skills below their linked attribute for one Advance, why not let them raise one skill below its linked attribute for half an Advance?
You can still rule that characters cannot raise the same skill twice in succession if you wish to retain the "raise two different skills" limitation, but allowing PCs to spend half an Advance at a time means there is the possibility for improvement every gaming session.
But that's just skills. Can the same concept be extended to attributes and Edges as well?
There have been several discussions in the past about the pros and cons of extending trait progression using d14, d16, d18, d20, d22 and d24, instead of applying fixed bonuses after d12. But what about inserting additional die steps in between the existing trait progression dice?
Introducing a d5, d7, d9 and d11 would allow characters to raise their attributes in smaller increments, for example a PC could increase their Strength from d6 to d7 for half an Advance, then increase it again to d8 with their next half Advance if they wished.
The same approach could be used for skills: if you had Agility d7 then increasing Fighting from d6 to d7 would cost quarter of an Advance, while increasing it from d7 to d8 would cost half an Advance.
Note that Derived Statistics are already rounded down (e.g., Vigor d12+1 gives Toughness 8 rather than 9), so increasing Vigor or Fighting to an odd die step would not be exploitable in that respect.
In Savage Abilities I introduced the idea of Minor Edges - Savage Worlds already splits Hindrances into Minor and Major, after all, so why not do the same for Edges?
Some Edges provide +2 bonuses which could be halved, for example a Minor version of Attractive might just give +1 Charisma, while a Minor version of Alertness might give +1 to Notice rolls.
Another option is to make an Edge more specialised, for example a Minor version of Alertness could grant its +2 bonus to one specific sense rather than all senses, while a Minor version of Beast Bond might apply to one specific animal rather than every animal under your control.
Other Edges provide multiple benefits which could be divided up, for example Beast Master might be split into Animal Empathy (animals don't attack you) and Animal Companion (you have a loyal animal companion), while Strong Willed might have its Intimidation and Taunt bonuses separated into two Minor Edges.
Particularly weak Edges such as Bruiser or Combat Reflexes could also be downgraded to Minor Edges, at the GM's discretion.
Characters can purchase a new skill at d4 for a full Advance, which effectively negates the -2 penalty for being unskilled. By extension, it should be possible for someone to become partially skilled (going from d4-2 to d4-1) for half an Advance, representing a character who is still learning the ropes but is no longer completely clueless.
Although this proposal has additional benefits (such as increasing character diversity by allowing smaller investments in specialised abilities), one of the main advantages is that PCs can advance in a more granular fashion. They can potentially gain or improve an ability every session, but overall they still progress at the same speed as the official rules.
From a terminology perspective it might be easier to refer to an Advance as a "Major Advance" and half an Advance as a "Minor Advance". PCs would then earn a Minor Advance each session, with two Minor Advances being worth a Major Advance. A Major Advance could be spent as described in the core rules, while each Minor Advance could be used for any or all of the following (at the GM's discretion):
- Gain a new Minor Edge, or increase a Minor Edge to a Major Edge (if two versions are available).
- Increase one skill that is equal or above its linked attribute by a minor increment (e.g., d6 to d7, or d7 to d8).
- Increase two skills that are both below their linked attribute by a minor increment.
- Increase one skill that is below its linked attribute by a major increment (e.g., d6 to d8).
- Learn a new skill at d4-1 (semi-skilled), or increase it from d4-1 to d4.
- Increase one attribute by a minor increment (this option can only be used twice per rank).
GMs using the "Spell Trappings" guidelines from Savage Spellbook might also allow characters to gain a single new trapping for a power they've already purchased with a Minor Advance. For example a character who had previously purchased New Power (with a Major Advance) to take Blast with the "Fireball" trapping could spend a Minor Advance to take "Ice Storm" as a second trapping for their Blast power.
Similarly, when using the "Skill Specialization" setting rule from SWD, one additional specialisation would cost a Minor Advance.