BDO isn’t a bad game imo, just very different from ToS.
Why don’t you play BDO now? You can buy it for $30, jump in and look around, enjoy the scenery, the quests, and leveling up.
There’s no level cap, so eventually you’ll get to a point where you’ll just grind levels, and money, and stuff to do bosses, and upgrade your gear. You can eventually play to a point where you just log on a few times a week to do bosses, grind a little, etc.
Similarly, you can play it alongside ToS, since most of your EXP is gained through daily missions, quests, pvp, dungeons, etc.
So both games can be played together. Ofcourse you can dedicate yourself to one to get further faster, but in the end, do what you find most fun.