Sounds great, right? 🙂
Since you are a vegetarian, a breakfast that would keep you full and give you enough energy would be something like muesli (you can add nuts or honey) or hummus / falafel.
Generally i love the arabic type of breakfast (was eating it daily when i was in Jordan) which is rich, tasty and can hold you full with energy.
If you prefer something light, and maybe sweet, then you could try greek yogurt with dried fruits and nuts, or even though all time classic energy meal, yogurt nuts and honey.
Last, but not least. I would recommend a very simple but delicious combination that a shepherd in Georgia once served me.
Heavy cream with honey. Its not a breakfast. Its an experience.
Closing, remember to eat clean food. What i mean is to avoid the trends which are products of marketing. Your body needs to know what it takes and the more complex food you add, the harder will be to digest and absorb the needed nutrients.
Avoid ingredients that you would not find naturally (coconut sugar is marketed as a healthy vegan sweetener, but its not a natural product. VEGAN beef burger seems nice but no one mentioned that its healthy).
Do your research. Plan ahead. Respect your food, whether its a lamb or a tomato.
Enjoy life even with regrets.