i'm new player too, (2 weeks old) and what i did was:
1. made my main til 120
2. made some characters for link skills (i made like 10 characters, all with important link skills like mercedes one that give more exp)
3. lvl all those characters to 120 for lvl 2 link skill
4. Lvl up my main or a mule to farm MP to 200
5. Basically all what Alex said, except for FPQ cuz, i'm a noob and i idk how to do it.
After lvling up all those characters, you should have around 200 red cubes or maybe more (will use them later) because of the farming, then i focused on getting my gear to have %drop rate til my total was 300% drop rate.
At this point, depending on how to lvled up, u should have enough points to buy at least 2 violet cube in cash shop/reward shop and sell them for 250m~300m each. Also you sell vp for 20m each. Never go lower unless you are in a hurry for the meso. By the end you will at least 500m~1b.
Now with the meso, you get yourself the sengoku/Japanese (clean) set for a relatively cheap price, a Fafnir weapon unless is too expensive then you will go for the Japanese one and lastly the accessories that are in this
guide (some of them you can farm them or get them at cheap price like Maple Onyx Gum (face) by trading maple leaf with the npc in FM, Aquatic Eye Accessory drop by zakum (eye) etc,). The only issue here are the rings and are somewhat expensive, you should get: tempest ring, solid gollux ring, cracked gollux ring and silver blossom ring, however, those are the cheapest compared to the others.
I think i should not remark again that you should get all those equips CLEAN, no potential or scroll on them unless it's cheap AF. When you get them all, you can start cubing with all the red cubes you farmed with each link skill character, you will have also Old maple Coins(can be used in the NPC in FM) in those characters to buy Premium Cubes to get to 3L potential in every equipment, and also to buy red cubes if you need more. Then you store all of them in Cash shop storage and transfer it to your step 4 character. Potential guide
here.
Now here comes the cubing session. You will start focusing on getting all the accesories to 20% drop rate (legendary), this includes only:
*4 rings
*necklace
*belt
*face
*eye
*earrings
*shoulder
so 20% each acc will get you to 300% drop rate. It will be far cheaper than buying one already with %20 drop rate. Does not matter if you're for example a warrior and get 20% drop rate and 18%int; with your other equipment you will focus on getting %main stat and %m/att for your weapon but you don't need them to be legendary, only until you can one-hit KO all the mobs in the MP - stronghold map (forgot the name). Your range should be somewhere between 100000~200000
With 300% drop rate you can do 2 things, farm or buy the familiar to reach to 600%, i prefer farming them, specially the mutant pig familiar because you also need Tiger Tickets to enter MP. So farm up in the mutant pig map and gather some familiar + tiger ticks.
And basically that's what you do to reach to 600% drop rate in a cheap/DIY method. To farm efficiently then you can sell your first 1-2 MP box for 125~130m and then get yourself a petvac to have faster runs.
To answer your questions:
does it take hundreds to get something to legendary with drop % (regardless of other stats)
It is not hard to get to legendary with red cubes because trust me, that's the only and the best way to get an item to legendary.
Is it worth doing MP without having much drop % (say just a familiar?
No.
would doing so take 10+ hours of grinding to even surmount to anything?
It's better to farm MP efficiently with 600% drop rate + petvac
It will take more time than buying but hey, this is a grinding game so have fun mapling (unless you can pay yourself some DP and sell them for 1:2.5b rate, hehe)