Do you think that solo lane Lulu should still be viable?
I really like to play Lulu but I hate playing support (bot lane). If Lulu is nerfed to the point that she is no longer a viable solo laner, I will be upset, as I will either be forced to go bot lane to play her, or stop playing her at all.
And frankly, I don't find Lulu to be incredibly OP on solo lane. Yes, she is somewhat annoying to deal with and non-interactive, but she isn't broken in the traditional sense. Solo lane Lulu is balanced by the fact that you are taking her mostly due to her utility, because you are otherwise better off picking other mages.
Let me explain: If you take her at mid lane, you must keep in mind that Lulu's damage is lower than the average mage. Not only she has only two offensive spells, but both of them have low scalings. They both have high base damage, which make them do good damage early, but at late game she is outscaled damage-wise by every other mage, and though her damage is still good against squishies late game, she struggles to do damage against anyone that has a single magic resistance item.
As for top lane, she is squishy. Generally you want a top laner that can be tanky. If you pick Lulu top, you are picking her because she can bully other top laners and still scale well as a protector late game. However, while she can be a bully early, she can't do much once the enemy buys a single magic resistance item. And most top laners outscale her in terms of tankyness, and many of them offer utility as well (ex: Malphite, Nautilus). You could build Lulu tanky to compensate that, but you could probably do better by picking a dedicated tank instead of her.
If you are picking Lulu you are picking her solely for her utility, which she technically does well, but on SoloQ, most teams can't take advantage of her utility. Are you really okay with her no longer being viable at solo lane?
if you are an AD assassin/bruiser,
if you are a short ranged mage or AP bruiser/assassin, or
if you are a tank.