Hello, I'm a ocasional european female diver who mostly dives while travelling (between 0-2 trips a year) and very rarely at home (Mediterranean sea). My trips are mostly to Asia or Egypt, I prefer to dive in warm water. For this reason, until now I have always been renting, but after 250 dives I've thought that maybe is the time to invest in a basic but quality dive gear that preferably doesn't break the bank. Because I mostly dive in other countries, light/easy to travel with is important. Also while on holiday trip I usually dive 3-4 dives a day, and after a while my mouth get tired, so maybe something lighter will be nice. Very important is that is reliable, sturdy and easy manteinance.
In addition to the Mk17Evo/C370, I'll also suggest you take a look at the Mares SXS 62X. It's designed for exactly your situation. Light, compact and with low profile second stages to minimize drag which should help with your jaw fatigue. You should also try different mouthpieces, it's very easy to change them.
I wouldn't recommend the second stages for really deep or cold water dives (the first stage can handle any recreational diving), but they are more than sufficient for your dives even if you start diving in the Med as well.