I think its perfectly fine to sell the logs when you need to. I look at it the same as cutting the grass on a new plot. Its a resource you own to harvest same as any crop. Nice new tractor!
The new tractor and productions look fantastic! You've really got things happening now, and I can see you being super busy with field work in the near future. Hopefully you can get as lucky with a harvester as you did the tractor. Good luck!
Hard work sure pays off! soo glad to see you get such a massive upgrade! really looking forward to see what this tractor can do and eager to learn all about productions!