It really depends what your individual treatment objectives are, ie symptom palliation, long term health, prevention of osteoporosis etc.
In terms of what is the most gentle, I would say the dose and route that achieves your goals with no negative effects. The lowest EFFECTIVE dose, as mentioned in treatment guidelines, is a good way of putting it I think.
Certainly undertreatment for someone who is symptomatic can be brutal, so I wouldn't necessarily think of the lowest available dose as being the most gentle.
Patches are probably a good choice if you are thinking about maintaining a relatively stable estradiol level 24/7 rather than swinging up and down on gel.
In terms of lifestyle, I personally feel that oral tablets are the least intrusive and time consuming, the most affordable for those who have to self fund treatment, and produce the least packaging waste so for me I could say this is the most gentle option.