For aesthetics it usually looks better to have a smooth bottom. In most cases it will not effect the liners fit of function. Upon new installation you may notice some inconsistency in the bottom as it's hard to install without disrupting the sand. Some of this will likely flatten out as the weight of the water acts upon the sand.
same as the bottom
You need water slippers to keep from slipping on the bottom of the pool floor.
Obviously the pool floor is not smooth.
Have a look at a Dragonfly Super skimmer it doesn't clean the pool floor but stops so much dirt from going down that you will hardly need to look at the bottom.
If this a newly built pool then have the company that built the pool ~ or the plasterer ~come back out and finish their job of prepping the pool before the start up. Whatever it takes to clear the main drain of the cement is their job and they have shirked their responsibility. If they say they have to drain the pool this then that will be at their expense. There should be no charge for this task and they should also pay for the water to refill the pool. k
Resurfacing is applying (troweling) a new coat on top of a eroding pool bottom. The best material to use is pool base (vermiculite and portland cement). It can be applied from 1/4" thickness and can be tapered to smooth edge.
Try casting a flocculant let it settle for a couple of days and then vacuum the bottom layer of water to waste you will see the layer you want to remove on the bottom of the pool. check with your pool shop for a good brand of flocculant.
Replaster the pool and keep the water chemically balanced (PH, alkalinity level etc..) this will keep the plaster from pitting thus keeping it smooth for a longer life.
As long as the floor: in other words, wall to wall.
Add the aluminum sulphate to the pool. Run the filter for two hours. Wait overnight to vacuum the bottom of the pool.
If your pool filter is up and running, also it is best to clean the walls and floor if you have a normal to high chlorine level because this will be also your cleaning agent. Take a soft bristle brush, get in the pool and start cleaning, all the above should come off. it is better if the filter is running so you can vac out the dirt, when the dirt goes to the bottom of the pool.
At the bottom of the pool.