Replacement for forerunner 245

I absolutely adore my forerunner 245 and have used it almost everyday for the last 6 years, however the battery life is starting to go and it will need replacing soon. Prior to this I had the forerunner 35 for about 4 years and loved it as well.

I've been looking at the newer forerunners, the 70, 170, and 570, but unsure which one would be best for me. Ideally I want whatever I get next to be my everyday watch for the next 5/6 years like the previous. I also have a small wrist and am worried about the newer models feeling bulky.

I run a few times a week and have gotten more into longer distances like half marathons in the past couple years. In the past I have done a few sprint triathlons and have been thinking about getting back into it. I also frequently go hiking and kayaking.