In the pipe industry, there are no general recipes for all forms of smoking pipes. Almost every form has its own individual characteristics.
The term "Stummels" in Russia means the wooden part of the smoking pipe. There are tubular forms in which the stem is noticeably longer than "Stummels". For example, the Prince. Your Dublin does not fit into any pipe-building standards. Therefore, it may be worth trying to make a stem whose length will be equal to the height of the bowl. In your case, the basic proportions of Dublin have already been violated, so you need to experiment and choose the length and shape of the stem that is most suitable for your pipe. Try cutting a stem out of a piece of wood and varying the length to see which length best fits your pipe.
Take one more tip. When we start cutting pipes we all dream of turning this world upside down. This is common to almost all novice pipe cutters. But do not try to create your first pipes by changing the classic shape of the pipes. They have already been perfected and verified to the millimeter over decades of their production. It is impossible for a beginner to jump over the creations of the great masters. If you want something new, create something new. Look for your shapes, but don't rework the classic ones.
When I started cutting pipes, I followed this path.
Here are some pictures of my first pipes.
Now I mainly make classics, but I can already afford to add something from myself to the classic form
Not having good skills in performing all work in pipe cutting, reworking classic forms is absolutely pointless. Working on new pipes should bring you Joy and enjoyment. If you do not feel this and work is just a headache for you, then you will not make a good pipe cutter.
Therefore, do what you like and do not listen to any advice, including mine. Do what gives you joy and pleasure. Sooner or later, the number of pipes you make will turn into their quality. The main thing is the satisfaction that work should bring you. If the work is enjoyable, then the pipes will start to turn out beautiful. Unfortunately, there is no other way.