as this would be a naturale choice from my point of view. Is there any deeper meaning in the preference for the decimal system ?
I'll highly appreciate your explanations and/or suggestions.
The number of satoshis in a bitcoin is arbitrary. People are accustomed to the decimal system and defining, for example, one bitcoin as 232 satoshis has no benefit over defining it as 108 satoshis.
From your point of view, why would a binary system be better?
You're right, the familiarity of people with the decimal system is a non neglible benefit for adoption, and I see that the used constants are choosen in a way, that the resulting numbers are nice looking in a decimal system.
On the other side, there are at least two points to mention, that are not beneficial.
First, most people will view as the basic unit of account one bitcoin, and one satoshi as some fraction of it. Using 8 decimal places will be much more most people have to deal with in their everyday life, and so - as they will use floating point arithmetics - they will come to the conclusion, that a bitcoin is infinitely divisible. As the minimum transferable ammount is one satoshi, this is not the case. Additionally it is therefore (luckily) not possible to increase the numbers of decimal places in a simple way, but this could lead to confusion in different ways. One user is disappointed realizing that he is not able to split his satoshi infinitely, the other one is thinking that bitcoin's value is overestimated, out of the same fallacy.
Second, more technically, other aspects like mining rewards and halving times have to be taken into account. By starting with a block reward not beeing a power of two, the next reward is not allways the half of the current one. Wich could lead to rumors that the algorithm does not work in the correct way because it is producing rounding errors and has to be adapted. By definig the first reward with 50 BTC and the time between halving with 210000 blocks the maximum currency supply is essentially given by mixing binary operations with decimal numbers, implicitly choosing the time between halvings in a way to get nice looking numbers, not economic senseful ones. By sticking strictly all parameters to powers of two a much more consistent description could be achieved and the available number space could be much broader exhausted.