I have enjoyed reading the thread but haven't replied before. Here's a mixed bag of comments and suggestions, all imo:
The basic changes seem a little too much. It's good that armor proficiency is gone but I'm not sure about the d6 for HPs. You say it's still less than clerics etc., but it is also as much as bards and rogues who are much more physical classes. I'd leave it at d4 and concentrate the benefits on spellcasting.
Lineages/affinities is a good idea. However, they should be kept really simple or the whole thing balloons out of proportion. I would give the special abilities at an even progression of levels such as 1, 4, 8, 12, 16, 20.
Even though I think the lineages should be simple, how about removing all class skills except the bare minimum (concentration, craft, spellcraft, profession) and instead let lineages give a couple of class skills?
The spell-like abilities have to go. It's too little to be really significant and adds a whole new set of rules.
I think the Strength of Magic ability should go as well, it's just too good and trespasses on paladin territory. I would actually prefer a fixed bonus to saves versus magic, maybe +1 per 3-5 levels.
How about introducing a little MAD? As it is, the sorcerer is really focused on only one stat with little meed for anything else. Specifically, how about giving bonus spells known for inherent intelligence? (I also think wizards should want wisdom and clerics should need charisma more, but that's not so relevant here.) I suppose this could be the standard rule for all cha-based (spontaneous) casters.
How about giving sorcerers access to their lineage spells a level earlier? Specifically, how about replacing the current progression for spells known with either the druid's or the wizard's progression for daily spells, requiring the first spell gained of each level to be the lineage spell. (The two progressions are almost identical, except the wizard's is capped at 4.) Using the wizard's progression would make a lot of sense if combined with giving bonus spells known.
Spell Evolution is an ugly mechanic. Only few spells belong to a path and few paths are complete (go all the way from level 0/1 to 9th). Until spells and chains are balanced, it's an ugly mechanic which requires another list and skews spell selection toward certain spells. For no real purpose when replacing spells is so much simpler.
If a nerf is needed (bonus spells known, even for intelligence, would be quite a treat), how about limiting the sorcerer's spell list to his spell known. This would bar him from using spell completion/trigger items with other spells, making scrolls and wands *much* less useful. Flavorwise, I think it would be a positive step to make sorecerers rely less on magic items manufactured by others. They could still use UMD, but it probably should not be a class skill.
Another possible nerf could be to a restriction on, say, the 4th spell known of each level, something like limiting it to spells 'similar' to the lineage spell. This would be simpler if the lineage spell was not one specific spell from a list but instead was chosen from a narrowly defined type of spell, such as 'fire based' or 'from the school of illusion'. It would take some care to define the groupings, but it would make sorcerers more diverse and make the class instantly compatible with spells from other sources than the PHB.
Can I propose a different mechanic for metamagic? How about allowing to cast a metamagiced spell without delay by sacrificing a spell slot of a level equal to the level adjustment? Of course he still needs to know the mm feat. This should probably just be an option available to all spontaneous casters, but sorcerers will benefit the most since they have many more spell slots than bards.
Instead of free detect magic, why not just increase the number of cantrips per day? Specifically, how about increasing the number of daily 0-level spells by the charisma bonus? This might be done for all casters or it could be a perk just for sorcerers.
Material components: Rather than granting Eschew Materials to some lineages, how about simply letting sorcerers replace inessential components with xp, say 1 xp for gp value, no minimum? It could be a basic trait of spontaneous casting or just for sorcererous spellcasting.
Phew!

Have these things been discussed before? I haven't read any of the previous thread.