Definitely agree - especially as I have advocated both as well for sovereigns. 
Specifically:
1. A life span for champions/sovereigns of about 200 turns (shorter than current) - randomed at 150+5*Con?
2. Maturity at age 40 turns. Sovereign starts age 40 turns. Champions are found with a random age of 40-100. Older Champions are cheaper to recruit. Age is a stat that can be listed only their main stat page.
3. Old age warning at 150. When they die they create a notable location (0) with a random weapon or armour or magic item of theirs.
4. If a Champion marries a champion, there is an X chance of a birth, but a 100% chance its a champion. A message is announced that a champion is being trained at age 20 turns, and appears in the city nearest to the mother at age 40 turns.
5. If a Sovereign marries a champion, make it a 33% champion, 33% channeler, 33% champion/channeler.
6. Make stats the mean of their two parents, with a "best of" rule for the most appropriate stat . (Ie, a lore-keeper is born, gets high Intelligence, etc).
7. BUT for essence, it's always "best of" + half of other parent (so this number should gradually increase, particualarly if your essence users start families). And, keeping with game trends, all channeller children get better natural regen, increasing a point a turn per generation (e.g., you regen 1 a turn, but your granddaughter goes 3 a turn). Essence used are total essence at the time of their birth, not starting essence nor essence at their maturity. E.g. instilling essence in your champions trying to conceive improves their offspring but worsens yours. (Darling, you seem to be lacking in essence this evening). Buf if you lose 3 essence to 2 champions, you get 2 champs with 3 essence and maybe a child with 4-5. Then two of them have children with 6-7 essence, etc.
8. Have starting sovereign (YOU) also die under these rules, except you can pass the crown down to a son (or daughter if you are egalitarian), who ascends and takes your name (think English Kings) so YOU continue. (ie, Steve the VI or Jo the III, etc as in Civilization). If you pass it down before you die, they get all your equipment, and half your experience (you retire to teach them), but you no longer exist per se and just get added to general population. This is an incentive to retire, but not to do so early.
9. If champions retire they beqeath similarly to their eldest son (or daughter if you are egalitarian), equipment and experience too, and the eldest can then decide whether to share that equipment with any other siblings!
10. Retirement can only occur in your ZOC (retirement on the battlefield often involves a pointy sword)
11. Mounts are not bequeathed. Gives them a (generous) lifespan too.
12. If you die without children, a champion steps up and takes your name (NPC you control with highest essence). If you have no kids or champions, your legacy ends as does your game!