Before anyone sucks or plays with my cock or I suck or play with a cock, I always request that if/once I do cum, that my cock be given vigorous postcum torture, so in any position, once I cum, I want him orally or with his hands to grant my request. Guys seem to love being granted that power of control over my cock, or at least they have always assaulted it with gusto.
Blowjob position depends on the situation. For GIVING (my preferred role) my fave position is to be backed up against a wall (preferably in the shower with hot water running (lightly, not full force, lots of hot steam misting the air), my head held against the wall, the cock thrusting in and out of my lips seeking its pleasure (but not gagging me), of course it is also a pleasure when he just stands still, grips my head and rocks my lips back and forth over his shaft until he gives up his cum. At other times, sitting in my armchair or couch, the guy straddling, positioning his cock in front of my face, I can lean forward and enjoy, explore his cock from balls to cockhead, nibble his balls, lick his shaft up and down, use my hands to stroke his shaft, suckle on his cockhead, he can thurst back and forth between my lips until his balls explode and deposit their cum blasting load into the recesses of my throat. OR, strip him, throw him on the bed naked, restrain him spread-eagled, his cock now mine to ravish, then with no mercy, use my mouth and hands to relentlessly make him cum. I like to orally (and manually) edge a cock, bringing it almost to the pleasure of a cum, but continually backing off not allowing that moment of joy. Eventually his balls will give up their cum, but since he is restrained, the fun continues. Conversely, instead of edging, the game is milking, going for as many cums as can be extracted (so many guys brag that no-one can drain their balls, well this experiment will see if that is true). Restrained he can't escape (other than by using his SAFE word), but most have an air of confidence that their balls are milk machines which can pump out cum no matter what I do. It makes for much fun and cum for both of us. (FYI, I've never yet successfully drained any balls dry, they always seem to expel at least a drop or a few, but I keep on trying.) I do enjoy the anonymity of gloryholes (though only use those in a sexclub - hard cocks thrusting out, dripping, throbbing, begging for all the oral and manual attention I can give it. It is always great when the guy being sucked gets so excited he begins thrusting his hips against the wall trying his best to get me to take more of his shaft, making that a moment to tease him by pausing and delaying the Big O he so eagerly desires (strangely, I've never tried the other side of a GH, maybe I just have too much fun being the cocksucker?). I haven't experienced this yet, but desire to be surrounded by a circle of horny hard men, and service each of their cocks, continuing around the circle until they are all drained (which my experience suggests may never happen, lol), and if I can't get to a cock in time, have it fountain, spraying me with its shower of pearls.
For RECEIVING, if he wants me to cum (which we both desire), my shaft has to be stroked during the blowjob, if no shaft stroking (I don't know why), my balls won't give up their cum.
I have always liked (not so much a position thing, but a "control" thing) to have a guy arrive, me standing hard and naked (or a least with my throbbing hung cock waving outside of my fly) inside, he slips in, strips his clothes, then kneels and ravishes my cock - it makes a great and fun way to meat a guy new to cocksucking my hardon, letting him know why he is there, to give my cock his undivided attention. It is always great to sit with my legs sprawled while he kneels or sits between them and gobbles down my cock. While he is sucking I might use my feet to grasp his cock and slide them up and down his shaft, as his head moves back and forth on my cock, hopefully he'll cum, lubing my feet (anytime a guy cums while sucking me, his suck action while he cums is always enhanced). Another favored position is to lay on my bed, with my legs wide (it is especially great if I'm restrained spread-eagle) and he ravishes my cock with his mouth, bringing me to multiple cums, being postcum tortured after each, and not relenting, nor allowing my escape, continues his oral and manual ministrations of my hostage cock (continuing until we are both exhausted, requiring food and/or sleep). I like being orally (and manually) edged or milked while in that restrained spreadeagle position. I'm always undecided should I watch or be blindfolded, both ways are fun, but such a pleasure to see his eyes and actions. If hiking, I like being backed against a tree and having a cock thrust in and out until it gains its pleasure (or having him either be against that same tree receiving my cock, or kneeling in front of me assaulting my cock), there is something special experiencing sex in the outdoors. I always enjoy being sucked in a sex club or bathhouse, being the center of attention with a circle of men surrounding us, jerking (and spraying their cum on us, bukkake anyone?) while I'm getting sucked (or doing the sucking).
Facials and/or the surprise of a Ruined Orgasm, should be part of both the giving and receiving play, while a sorta waste of good cum, they do add variety and fun in getting or giving a blowjob.
I'd like to experience group sex, both sucking, being sucked and watching all of the surrounding action, I'm sure such a fun experience would introduce new positions which I have not tried nor imagined.
Any position will do, when you get down to it can there be a bad position, but these are my some of my favorites, positon can heighten the fantasy of the blowjob, and enhance the pleasure. I just like cocksucking, receiving or giving, though if I were limited to only do one or the other, I'd choose being the cocksucker, any cock should beware should it gain my attention.
I look forward to hearing (and learning from) the experiences and desires of the rest of you, always like to explore new "positions".