Tiny Creature Combat and Flying Acrobatics

I would like to level the battlefield for the little ones. Tiny creatures have a reach of zero, so they normally have to enter an enemy’s square to attack, which makes them subject to Attacks of Opportunity (AoO) from for example a medium foe with 5 foot reach. This puts them at a significant disadvantage in combat, which they can try to remedy with the help of a couple of rule adjudications. The first option seems simple enough; use a reach weapon, but if read by the letter, a reach weapon doubles your reach, which does not do much for zero reach. I would suggest ruling that a tiny creature with a reach weapon has 5 foot reach (This ruling has been affirmed by the developers).

Light and Darkness Rules

These are alternate and I think superior rules governing illumination. The goal is to have darkness be dangerous without being completely deadly to characters without darkvision, and still have Darkness spells be useful to dark dwellers.
I operate with three levels of illumination: Light (no concealment), Dim Light (concealment 20% mischance), and Darkness (total concealment 50% mischance).
I do not give "Bright Light" its own illumination category, because it is has the same concealment properties as Light, and that is what illumination is about. Whether the light is hurtful to a creature's eyes is a separate issue.
We all have a pretty clear idea of what happens when we light a torch in the dark, and the standard rules work fine for mundane light. A torch creates 20 feet radius of Light and an additional 20 feet of Dim Light. The problem occurs when we introduce magical light and darkness.

Darkness Spells

They look very similar to the standard versions, but have been changed slightly because the standard rules for how magical light and darkness interact were unbalanced. So here are the rules I recommend for magical light and darkness.

Darkness
School abjuration [darkness]; Level bard 2, cleric 2, sorcerer/wizard 2
Casting Time: 1 standard action
Components: V, M/DF (bat fur and a piece of coal)
Range: Touch or 25ft + 5ft/2lvl
Target: 20ft radius area
Duration: 1 min/level (D)
Saving Throw none; Spell resistance no
This spell has two uses, first it can causes darkness to spread out from object touched to a 20-foot radius. The area is impenetrable to mundane light, and lower level magic light create only shadowy illumination in its normal light radius and nothing beyond that. Daylight (spell) functions normally in the area of darkness, except it does not hurt light sensitive eyes within the area of the darkness spell. Darkvision functions normally.
Alternately Darkness can be used to dispel any one light spell of equal or lower spell level within 25ft + 5ft/2lvl.

Deeper Darkness
School abjuration [darkness]; Level cleric 3
Casting Time: 1 standard action
Components: V, M/DF (bat fur and a piece of coal)
Range: 25ft + 5ft/2lvl
Target: 60ft radius area
Duration 10 min/level (D)
Saving Throw none; Spell resistance no
This spell causes darkness to spread out from an object to a 60-foot radius. The area is impenetrable to mundane light, and low level magic light. Daylight (spell) creates only shadowy illumination in its normal light radius and nothing beyond that. Darkvision functions normally.
If targeted Deeper Darkness can be used to dispel any one light spell of equal or lower spell level.

NB I created a new cantrip: Extinguish