messing with load order then trying to load a save is never a good idea. yes if you plan to move around your load order, be prepaired to make a new game. non-esp mods typically can be moved around in the load order without issue, but if it had an esp and u move it about it can throw a hissy fit and straight die.
if u want a better illustration of what im talking about download wryebash and look at the save collum. if its purple ur set, green is good but some minor issues are present could kill the game 40 hours later for example, or could last a good 100 before u ever saw an issue, orange prolly means ur game is guna die a slow lingering death id be suprised if u make it more than 20 hours in orange b4 crashing out, red means ull be lucky to even load into the game. moving one file with an esp from one slot to another in your load order typically will jump u straight from purple to orange if not red. purple to green typically seems to happen when u get an autosave/quicksave corruption. orange and red like i said typically mean u messed up ur load order. now to be fair if its a minor change and skyrim is able to reorder your load order in game and complete a clean save its possible that while u may have loaded a orange save file the next save could be rendered as a purple or even green. i dont fully understand it enough to teach though so ull have to do some research to find the limitation of skyrim and rebuilding the load order in a new save. ill go out on a limb and guess that script heavy mods are a no go to reorder since they may be between drawing from the script when u save and i duno might just cause the whole skyrim universe to burst into flame.
one final tip for load order and this certainly isnt any hard rule. i tend to load all my nexus mods first. your frameworks, skse, ui stuff first sense everything plays on those kinda mods. then your nexus mods follower,armor,weapons, w/e. those tend to be fairly stable and if you run into an issues its typically a simple fix. loverslab mods i run last starting with sexlab, arousal, and zaz. loverslab mods tend to argue and bicker over master load order that your going to have to manually fix with tes5edit. also if your going to have a CTD issue, its likely going to be one of those loverslab mods that just wasnt correctly packaged or is conflicting with a nexus mod they never tried before. so add em 1-3 at a time and if u hit an issue stop, remove them, and readd one at a time to find the trouble then find the conflicts and resolve them.
best of luck.