21, 2 kids, needing a better BC

Ive had the implanon since my 1st child, (removed it to get pregnant w 2nd then put back in after birth) pre pregnancy weight b4 my 1st was ~140. Currently i am ~195. Im wanting to switch bc i have gained way too much weight & it is hard for me to loose it. Also, my period stopped for about 4mo then came back but it wasnt a normal flow like normal colored blood, it was more on the brownish side. Just wanting opinions on different BC methods that wont cause me problems. help!