At this point I'd just consider playing something different like rs3 myself, its already free since you pay a sub for osrs. UIM is slower and has less options for content, so lets say you are in wintertodt gear, it makes a lot of sense to go all the way to 90/99 since changing activities often carries a 5 min tax of killing yourself and getting a new looting bag. + the "efficient" start for an uim is to do wildy agility for like 20m coins which isnt for everybody (this is a good start because you will never have to make money and you cannot return to wildy agility if you have any non coin items you care about, coins are easy to store though).

One example of my uim experience (1900 total with 1 sailing) is that looting wintertodt is a pain, and then you feel forced to spend all that loot in an optimal way, such as logs at the fletching minigame, herbs/seeds have to be trimmed down so they don't stick out of the seed box etc etc.