Just converted a Euro Keg, General Advice

Yesterday I obtained a keg from local beer distributor. I assume it is a Euro because language appears to be German and has 50L stamped on side. This sucker is heavy. I used a grinder to remove top. Look pretty good except I need to polish sharp edge. I used a step bit from Lowe's to drill 2- 7/8 inch holes for spigot and thermometer. I my have burn the bit (used oil to cool).

Questions:
I drilled the spigot hole above lowest weld. This is about 2 inches from bottom. I looks like I will have at least 1/2 gallon below spigot. Should I have dilled trough weld to lower the hole. Will this limit it's use for only heating water? I would lose a lot of wort otherwise.

What is a easy way to soften cut edges?

Is an standard "American" keg easier to convert?

You'll have to run a tube from the spigot to the bottom of the keg. once you start draining your keg, this will siphon out almost all the liquid in your keg. Do some searches and you'll find different ideas for siphon tubes.

Keep in mind a Euro keg is smaller than a sanka. Not sure the amount but I would guess about 2 gallons smaller.