The feature feels abusive since you can save constantly making some of the game design feel weak. I want the game to be challenging but not impossible.

this is indicative of a more fundamental gameplay design flaw. if the ability to save has any impact whatsoever on gameplay, there's something wrong with your gameplay.

making it to the savepoint is not a challenge, its punishment - as mentioned above.

You want the player to WANT to be able to save at any time, "cause this is so cool! and i might die! or miss something! , and i have to go to the bathroom!" . <g>

add the ability to save at any time, then get your gameplay to that level of engrossment. it can be done, be creative - but not hokey. this assumes of course that you've made a game type that can generate that level of engrossment in the first place. not all gametypes do. but you'e doing an RPG, so no worries there. sounds like a "level" is too easy if you can save all the time. is that what it boils down to?