There are many reasons for limiting battle scanner range:
1) Long-range battle scanners mess with AI priorities (so they act stupid)
2) Long-range battle scanners bug out and give you permanent vision of aliens that were tagged (and rarely cause unstable reloads sometime ruining a campaign)
3) The aliens have no counter to long-range battle scanners
4) Long-range battle scanners give you the vision that allows effective alpha striking (which we try to avoid)
5) You can attack aliens at long-range and they cannot respond (and often won't respond effectively)
6) It can be unfun and lame. One of the last things jl- did on LW 1.0 was "improve" the AI by making them less likely to charge blindly into your overwatch traps. The problem with this is sometimes they'll just sit there when they can't see you. Makes it really easy to battle scan them and snipe them (which is lame).
Scouting in general is good to get an idea what's out there, but you don't want to know everything from a gameplay perspective. It makes for a lot more engaging battles when you don't know what's out there. Watch some LW 1.0 playthroughs past the mid game. If players are smart they bring tons of battle scanners and do very strong alpha strike initiations. It can be really monotonous and anti-climatic. Sometimes I even feel sorry for the aliens.
That being said, you're welcome to mod whatever you like but those are the reasons for the significant reduction in battle scanner range in the rebalance.
Right now, battle scanners are useful for peaking around corners, over ledges, and revealing cloaked units. A scout with bombard gets a 'little' bit of scouting with them. That's all we really want them used for. We've tried various ranges but the cons seem to outweigh the pros when increasing the range. The boost to scouting in 1.18 was with elerium batteries. Changes to the battle scanner would more likely be a range decrease than an increase.
So, in short, to answer your question: Yes, we always everything (as I'm often wrong about things), but we've done a lot of tests and played with a lot of different ranges on the battle scanner so I don't foresee us increasing the range.