Doing things that way would create a lot of challenges right off the bat:
Magic:
1. First level spellcasters would be even weaker than usual. In ordinary 3.x, a wizard or sorceror (and to a lesser degree, a cleric or druid), can cast between two (generalist wizard and four (sorceror) spells before having to go cower behind a rock. By eliminating the possibility of bonus spells for stats, you reduce this to one (generalist wizard) to three (sorceror).
2. By reducing the DC of most spells to 11, you would ensure that the one or two spells would stand a good chance of doing nothing if they have a save, thus skewing the spell choice of low level characters towards spells like Enlarge Person, etc that don't have saves.
3. By ensuring that non-healing domain clerics can only cast one CLW per day, you would make sure that the party has to spend several days to recover from any battle where multiple PCs are knocked unconscious.
Skills:
By eliminating the possibility of first level bonus skill points for high int, you hurt wizards a lot. You also limit the variety of rogues and clerics that are possible in your game and ensure that fighters will never have ANY skills (one of the small boons given to fighters who start with a 12-14 int is that they can actually get some decent skills by buying them cross-class). You also magnify the significance of the human bonus skill point/level because that is the only way any character can start off with more than the minimum amount of skills.
Combat:
1. You really hurt fighters and paladins (and barbarians to a lesser degree). At first level the usual difference between a fighter/barbarian/paladin and a cleric or rogue in terms of combat ability is primarily generated by their stats. A fighter who starts with a 16 strength will attack at +4 (+5 with weapon focus) and deal 1d8+3 damage with his longsword. The cleric might start with a 14 strength and thereby attack at +2 for 1d8+2 damage. A wizard would probably start with a 10 strength and attack at +0 for 1d6 damage. Starting all stats at 10 or 11 flattens this out. The fighter attacks at +1 (+2 with weapon focus) for 1d8 points of damage. The cleric attacks at +0 (+1 w/ War domain) for 1d8 points of damage. The wizard attacks at +0 for 1d6 points of damage. So with this, rule, at first level, the fighter would not be nearly as much better at fighting as he usually is.
2. Barbarians would be hurt the same way all fighter types are--with one exception. When they raged, they would not just be 1.5 times as effective in combat, they'be be closer to 2 or 3 times as effective. The difference between attacking at +1 for 1d8 points of damage and attacking at +3 for 1d8+2 points of damage is huge.
3. Paladins are denied use of their (admittedly weak at low levels) smite ability. Ordinarily they smite evil for something like +2 or +3 to hit and +1 damage at first level. Under this system, they'd smite at +0 for +1 damage. That's not much of an ability.
4. Rogues would be screwed at low levels by this change. Typically, a first level rogue has a similar or better AC than the first level fighter. The rogue might have a 16 dex and wear leather armor for AC 15 or he might be a halfling with an 18 dex and a chain shirt for AC 19. In the same way, the fighter might wear splint mail for AC 16 or wear chain mail, carry a heavy shield, and have a +2 dex bonus for AC 19. Under this system, the rogue would have AC 12 while the fighter still has an AC between 16 (splint mail/scale mail+shield) to 19 (chain mail and tower shield). That rogue had better stay out of combat--especially if the cleric only has one cure spell per day (that he might have already used for something else if he cast bless for instance)).
At high levels, you would see problems in different directions. It would be very very difficult to make an effective paladin or monk since they depend on having multiple ability scores at decent levels. The 8th level monk could have an 18 wisdom, 10 strength (so he won't hit and when he does it won't hurt his foes), 10 dex (so his AC is still poor and he doesn't qualify for very many feats), 10 constitution (so he can't take hits either), etc. A 12th level paladin could have a 16 strength and charisma but only at the cost of a 10 constitution (so he has few hit points) and 10 wisdom (so he can't cast spells). Not until very high levels would balanced characters be possible.
Conversely, spellcasters could achieve hideous things if they somehow managed to survive until high levels. The base int of a 20th level wizard would be 31 before his +6 headband and +5 tome were taken into account. with an int of 42, such a character would have a base save DC of 26+spell level, making the DC of a 9th level spell 35. (37 with greater spell focus). That's significantly higher than most high level wizards have.
I'd advise you to toss out the idea and come up with something else. It disrupts the D&D system at so many levels, that you'll have to redesign nearly everything to make it work.
