What do you mean by this?

Barton Fink is as invitingly allegorical as Eraserhead, no? You either accept it on its own terms or you don't.

I don't really see a need to compare the two films, nor the filmmakers behind them. Other than, perhaps, narrative pattern: moderately weird first and second acts followed by a seriously surreal and chaotic final third, at which point the viewer is either drawn further in or loses interest completely.

There's sense behind Eraserhead, though...

I disagree with this.

Lynch isn't putting together "random bits with little purpose". Though he might work more intuitively than the Coens (or any other filmmaker), it's not really random at all. Each of his scenes, even the unscripted ones, are set up to specific lighting requirements, with consciously chosen locations, with actors consciously casted in certain roles; then when he pieces it together in the editing room he's not leaving anything to chance - there's a conscious decision being made with each and every cut, dissolve or other transition. Like any artistic judgement, there's a reason, conscious or not, why you'd juxtapose this image with that image (for instance), why you'd go in for a close-up there and not an establishing shot, why you'd play this music or that music over certain types of images.

Random's an odd word when describing a product of conscious decision-making.