Welcome to Susbim matey.
The Type 2 is a fun little boat but as you have found very limited.
If you are starting from Kiel then use the canal.
This will cut your distance to travel to the North Sea. Before leaving your mooring, look at the Nav Officers orders and under Plot Course you will find an option for Kiel Outbound, click on it and the course will be plotted for you.
Then set speed and choose Follow Plotted Course.
When you are under way, play with your speed settings while asking the Nav Officer for 'Max Range at Current Speed'. By doing this you will be able to find the optimum speed for the Type 2. For the Type 2 it is probably somewhere between 4-6kts.
As for completing your assigned patrol orders (Patrol Grid XXXX for 24hrs) that is entirely up to you. You will loose a renown bonus if you don't complete your 24hr Patrol and then return to base (without warping) but if you know of a Ship Rich area where you think you can get better results then the decision is yours Captain.
Enjoy your first trip through the Kiel Canal and enjoy the GWX Experience.
Please come again, thank you!:rotfl: