Siam Heritage is my go to at the moment in Silom. The rooms are a decent size, and have basic cooking facilites, not that I use them much but it is nice to have the option if you can't be arsed going out.
I think the reception area changed a few years ago and now you you just walk past the reception to the lifts at the back. The reception is in a kind of separate glassed off bit at the front and you don't have to interact at all. There are restaurants in the enterance so people coming and going all the time. There is even a handy little bench by the key card glass doors by/ for the lift area for a boy to wait on whilst you come down to get him. The bench is out of sight from the reception. There are restaurants in the entrance, so people are coming and going all the time. go-to The rooms are a decent size and have basic cooking facilities, not that I use them much, but it is nice to have the option if you can't be arsed going out.The reception is in a kind of separate, glassed-off bit at the front, and you don't have to interact at all.
I am there in early October, and it was £35 a night for their middle-grade room option.