There are exactly 4 spare T1k and T5k in the set which are used to colour up the 500s
But you should never color-up with chips that will be colored off. Two reasons: 1) it's inefficient to introduce chips that will be removed later anyway and 2) per definition you don't need more T1000, because if you needed more they would have been in the starting stack.
I'm not saying that using the 4 spare T1000 will ruin the night

, but I'm just pointing out that while it sounds neat in theory, it's not a practical feature of this breakdown.
Usually it is an unwanted inefficiency but with the small addition of some T500 the set is able to support smoother early level transitions. An inherent problem with T100 is that the starting blinds of 100/100 have to double to get the next level or you need more chips to give out 20k starting stacks.
I think I see what you mean. You mean having 1000/2000 as level 1, then 1500/3000 as level 2? Yes, this is a benefit of T500 base. The equvalent of a T100 base would be 200/400 as level 1 then 300/600.
It very common to compare apples to oranges when comparing blind structures. Like you're comparing to 100/100, that only works if you intend on doing 500/500 in a base T500, which I guess you're not since you speak of "smoothness"?
To compare apples to apples:
| Base 100 | Base 500 |
| Lowest possible levels, no lopsided levels: | L1: 100/200
L2: 200/400 | L1: 500/1000
L2: 1000/2000 |
| Lowest possible levels, lopsided allowed: | L1: 100/100
L2: 100/200 | L1: 500/500
L2: 500/1000 |
| Lowest possible levels, no doubling, lopsided allowed: | L1: 100/200
L2: 100/300 | L1: 500/1000
L2: 500/1500 |
| No lopsided, no doubling | L1: 200/400
L2: 300/600 | L1: 1000
L2: 2000 |
If you're in the "no doubling, no lopsided" camp, then yes, 1000/2000 is more natural than 200/400. (Of course, the T25 base equvalent of 50/100, 75/150 is pretty natural as well, just sayin).
But just to be clear, every single breakdown known to man allows for a smooth progression.
The con, I believe, with L1 1000/2000 is that the T500 is only used for a single level, namely L2 1500/3000. One could argue L4 2500/5000, but that level is rarely needed/used in a home game. Speaking of "efficiency", it's a bit of a waste to buy chips for a single level in my opinion.
Which starting levels are you envisioning to use?