Small cars generally have smaller wheels so I'm guessing your rolling 13 or 14 inch rims which will be around 4.5 inches wide,
This is great for speed but means its easier to sink the whole wheel in to a drain where before you maybe had tyres that were up to 8" wide and would handle a drop much easier.
In any case where possible I highly recommend you avoid drains, speed ramps at over 10mph and pot holes,
Things like this buckle your wheels and off set your tracking,
This is why your car is pulling to one side,
Its because one of your wheels is buckled,
I highly recommend you go to a tyre fitting place they will diagnose what wheels are buckled and repair the buckles aswell as laser align your tracking,
Now a buckle could be 30 pounds to fix,
But your car will feel much better when fixed, your shocks will last longer and your mpg will increase slightly because you will be rolling on circles again instead of blocks.
It's only pulling to one side when I hit a drain. If the drain hits the drivers wheel, the car shoots to the centre of the road. It's impossible to avoid all drains, they're everywhere.
Apart from that the car drives fine.