Hey there Gez,
First of all, I want to let you know that I really like the versatility this variant fighter offers.
I showed it to my DM, however, and two minutes later, he said "too much that you can powergame with." So, of course I asked how, and this is one example. Human, your variant, let's go with level twelve.
Ok, this gives us 8 bonus feats, including extra feat at creation as a human, or 6 feats and 2 stunts, in addition to 5 feats from leveling (for a total of 13 stunts and feats combo). Let's assume a high dex warrior, so he takes weapon finesse, for times when he has a light weapon to utilize to it's max, and weapon focus great sword, because those are just good. Then at level 4, he specializes in Great sword. Now let's go for monkey grip because he wants a shield as well. These Are the important ones in the beginning, then you can fill others up with the power attack cleave tree are even two hand fighting tree (actually you can take power attack, cleave, and the three two weapon fighting feats to fill up to level 12 feat potential). At eighth level, he takes the graceful combat stunt. Then at 9th greater weapon focus great sword, and at twelve of course We take twin weapon stunt, Buy a second great sword, and there is a feat here to spare as well, so take greater weapon spec great sword.
Ok, so now we have a very dexterous fighter wielding two great swords, one handed, with little or no penalty (depending on the feat tree he took), and potentially power attacking like mad. Since he focused on dex, he has potentially good ac as well. Then at 16 he could take flurry of strikes, which gives him extra attacks, with a small penalty, but his attack bonus should be able to support it. Or he could take Weapon mastery, which adds more attack bonus. Obviously you will have dex bonus, magical enhancements, and such to add, so my DM feels this is a slightly broken path.
If I did my math right, the six attacks at 2d6 damage each (again assuming the lvl 12 fighter) are at +16, +11, +6, +16, +6, and -4. I am assuming a good dex, but let’s say it is 18 so +4 on each, and let's assume +2 straight enhancements on each sword. I don't think 22,17,12,22,12,2 is bad at level 12. If first five hit, you have base damage well into the thirties, before magic bonuses, ability bonuses and whatnot. I think an average round of damage for this would be around 60 or so, let's not think about crits. I know some of this doesn't sound too bad, but throw in power attack, and crits and you are dealing a lot for your level, I think. So this is the first way he thought of breaking this combination, and honestly he came up with two more, but this is only one i could remember.
If I have made any math mistakes or blunders in using your alternate progression, please do correct me. As I said, I liked your variant, but as it stands, my DM won't let it fly. :\
First of all, I want to let you know that I really like the versatility this variant fighter offers.

I showed it to my DM, however, and two minutes later, he said "too much that you can powergame with." So, of course I asked how, and this is one example. Human, your variant, let's go with level twelve.
Ok, this gives us 8 bonus feats, including extra feat at creation as a human, or 6 feats and 2 stunts, in addition to 5 feats from leveling (for a total of 13 stunts and feats combo). Let's assume a high dex warrior, so he takes weapon finesse, for times when he has a light weapon to utilize to it's max, and weapon focus great sword, because those are just good. Then at level 4, he specializes in Great sword. Now let's go for monkey grip because he wants a shield as well. These Are the important ones in the beginning, then you can fill others up with the power attack cleave tree are even two hand fighting tree (actually you can take power attack, cleave, and the three two weapon fighting feats to fill up to level 12 feat potential). At eighth level, he takes the graceful combat stunt. Then at 9th greater weapon focus great sword, and at twelve of course We take twin weapon stunt, Buy a second great sword, and there is a feat here to spare as well, so take greater weapon spec great sword.
Ok, so now we have a very dexterous fighter wielding two great swords, one handed, with little or no penalty (depending on the feat tree he took), and potentially power attacking like mad. Since he focused on dex, he has potentially good ac as well. Then at 16 he could take flurry of strikes, which gives him extra attacks, with a small penalty, but his attack bonus should be able to support it. Or he could take Weapon mastery, which adds more attack bonus. Obviously you will have dex bonus, magical enhancements, and such to add, so my DM feels this is a slightly broken path.
If I did my math right, the six attacks at 2d6 damage each (again assuming the lvl 12 fighter) are at +16, +11, +6, +16, +6, and -4. I am assuming a good dex, but let’s say it is 18 so +4 on each, and let's assume +2 straight enhancements on each sword. I don't think 22,17,12,22,12,2 is bad at level 12. If first five hit, you have base damage well into the thirties, before magic bonuses, ability bonuses and whatnot. I think an average round of damage for this would be around 60 or so, let's not think about crits. I know some of this doesn't sound too bad, but throw in power attack, and crits and you are dealing a lot for your level, I think. So this is the first way he thought of breaking this combination, and honestly he came up with two more, but this is only one i could remember.
If I have made any math mistakes or blunders in using your alternate progression, please do correct me. As I said, I liked your variant, but as it stands, my DM won't let it fly. :\