I have no problem with restricted use of deepstrikes, with a 2 hex-deep limit. It is consistent with logic of an LOS rule. If there are no restrictions on deepstriking, you might as well not have an LOS rule at all. There is an internal logic there that I think is undeniable.
If you want a simple rule set, nothing is simpler than LOS. Deepstriking is always going to have a layer of restriction on it as people don't want hexes flipped, planets flipped, or bases flipped without the work to get to that hex, so by definition deepstriking will always have more rules to it than a simple LOS.
I could make long conjecturable arguements about space and defenses, etc, but I will simply say this. If you can merely pass through a hex that is not yours, then DV effectively means nothing. It is no mistake that there are mandatory missions in neutral and enemy hexes.
Further, those races that have expendables as a primary weapon get magic replenishment of those assets which is not accurate nor fair, therefore the LOS rule is meant to constrain that error in Taldren's expendables system
Finally, if deepstriking is restricted in some manner, then it is likely merely to be a nuisance and a source of more rule-debating and flames whereas LOS is transparent and fair. Can we imagine the first instance where some deepstriker crashes through no fault on his own in a mission with a significant force sent to intercept him?? That kind of system will merely sow the seeds of distrust. Hell, we had people crapping themselves over supposed purposeful disconnections on RDSL. Can you imagine the flak that will ensue when this happens to a deepstriker whether or not it is intentional?
BTW, It is a total misnomer that any front is protected under LOS. One need merely build an LOS to it.