This code reworks the physique traits and pure blooded so that they give a boost to children and adults, but not elderly people, reducing the in-game age inflation. Doing so for other traits like blademaster might be a worthwhile idea, it's as easy as copy-pasting the child_health adult_health sections and changing the number

# Physique (+1) - Hale
physique_good_1 = {
opposites = {
weak
spindly
physique_bad
physique_good_2
physique_good_3
}

prowess = 2
child_health = 0.30
adult_health = 0.25

birth = 0.5
random_creation = 0.5

attraction_opinion = 5

culture_modifier = {
parameter = strong_traits_more_valued
monthly_prestige = 0.25
}

group = physique_good
level = 1

ruler_designer_cost = 60

desc = {
first_valid = {
triggered_desc = {
trigger = {
NOT = { exists = this }
}
desc = trait_physique_good_1_desc
}
desc = trait_physique_good_1_character_desc
}
}

ai_energy = 10

genetic = yes
physical = yes
good = yes
}

# Physique (+2) - Robust
physique_good_2 = {
opposites = {
weak
spindly
physique_bad
physique_good_1
physique_good_3
}

physical = yes

prowess = 4
child_health = 0.65
adult_health = 0.5

birth = 0.25
random_creation = 0.25

attraction_opinion = 10

culture_modifier = {
parameter = strong_traits_more_valued
monthly_prestige = 0.5
}

group = physique_good
level = 2

ruler_designer_cost = 120

desc = {
first_valid = {
triggered_desc = {
trigger = {
NOT = { exists = this }
}
desc = trait_physique_good_2_desc
}
desc = trait_physique_good_2_character_desc
}
}

ai_energy = 20

genetic = yes
good = yes
}

# Physique (+3) - Amazonian (f) / Herculean (m)
physique_good_3 = {
opposites = {
weak
spindly
physique_bad
physique_good_1
physique_good_2
}

birth = 0.15
random_creation = 0.15

prowess = 8
child_health = 1.25
adult_health = 1

attraction_opinion = 15

culture_modifier = {
parameter = strong_traits_more_valued
monthly_prestige = 1
}

# amazonian if female
# herculean if male

ruler_designer_cost = 180

name = {
first_valid = {
triggered_desc = {
trigger = { NOT = { exists = this } }
desc = trait_physique_good_male_3
}
triggered_desc = {
trigger = { is_female = yes }
desc = trait_physique_good_female_3
}
desc = trait_physique_good_male_3
}
}

desc = {
first_valid = {
triggered_desc = {
trigger = {
NOT = { exists = this }
}
desc = trait_physique_good_3_desc
}
desc = trait_physique_good_3_character_desc
}
}

group = physique_good
level = 3

ai_energy = 20

genetic = yes
physical = yes
good = yes
}

################# PHYSICAL (GOOD) ################
pure_blooded = {
physical = yes
fertility = 0.1
child_health = 0.30
adult_health = 0.25

inbreeding_chance = -0.5
inherit_chance = 15
both_parent_has_trait_inherit_chance = 100
good = yes

ruler_designer_cost = 50

desc = {
first_valid = {
triggered_desc = {
trigger = {
NOT = { exists = this }
}
desc = trait_pure_blooded_desc
}
desc = trait_pure_blooded_character_desc
}
}
}