Not straightforward answers I can give you. It all depends on ... what you want.
If a Bombay Saphire is your thing, here is a link in which contains info on that recipe. Read Old Dog's posts. His wife likes this and she is Dutch, so it should be fine!
http://homedistiller.org/forum/viewtopi ... 11&t=10203
Trick to a Bombay style is you vapour infuse all of the ingredients.
If you decide to go the other way and distill with herbs/berries in the boiler, you will get a fuller taste. But if it is Gin/Tonic you are after, that may not be needed.
More citrus is okay, especially in a Gin/Tonic. Saves you on having to buy lemons!
But ... not so much citrus as in Violent Blue's original post. Much less!
If you want to partially distill with berries in the boiler and then vapour infuse the rest that's okay. Pretty much everything can be put in the boiler. Only citrus ... is better vapour infused. You could distill with the berries in the boiler. You could vapour infuse. First is heavier, second is lighter. In whisky terms, just to make a comparison, think "single malt" vs. "blended".
If you macerate and take out herbs/berries before distilling, go for a maceration time of 1 to 2 weeks. If you distill with herbs/berries in the boiler, just macerate for in between 12 and 24 hours prior to distilling.
Always buy fresh juniper if you can! It gives off twice the amount of taste. If not quadrupel. Dried variety gives of much more tanines.
Macerate at 43% with crushed berries. Or macerate with uncrushed berries at 60% abv, then dilute to 30% and distill. But the only time you don't crush berries is when you boil them in the boiler. If you don't boil the berries in your boiler, always crush.
Okay, here is what you should really do: type in something like "genever" or "geneva". I have some post with the abundance of info you might be looking for.
Or take a shortcut. Add 20 grams of lightly crushed berries and 10 grams of ground coriander and 3 grams of citrus peel to 1 liter of 60%. Let it sit for one week. Filter. Dilute to 30%. Distill.
It will probably give you just what you want in your Tonic!
Good luck, Odin.
"Great art is created only through diligent and painstaking effort to perfect and polish oneself." by Buddhist filosofer Daisaku Ikeda.