Engineer Woes

So, i've been playing a fair bit of Team Fortress 2 lately, and usually end up as an engineer. Now, I usually play Arena, so the highest points for each class isn't great. The highest i've got is 34 on a Pyro on a practically empty payload server where I managed to move the cart all the way in 1 life and kill a few people. But second is the engineer, where i've managed 12 points.

While I'd like to play other classes, I just seem better with the Engineer, I can't think of many situations where I can't cause the most pain to the other team with a different class, but that's maybe cos I know what i'm doing with an engineer the most.

Unfortunately there are a few things that make playing an Engineer really difficult, I know I can do something about them (like not playing an engineer on a certain map) but it doesn't stop me getting a bit annoyed.

1) This map doesn't have easy to get ammo boxes. Like Watchtower, to be any use in early game I need to drop a sentry, which means I can't drop a Dispenser at all, nor can I upgrade the sentry. The major worry is that i'm not as useful on this map as on other maps, especially due to the layout of Watchtower making a good sentry location very tricky.

2) It's nice that you're shooting before the match starts, especially when you're a soilder and we don't have a medic. The game starts and I drop a sentry and go to pick up the box of ammo at the start, but you've already picked it up... This also goes for a bit later when I drop a sentry, pick up ammo, drop a Dispenser, then go to pick up more ammo, and some sniper or other has just picked it up, can people really be struggling for ammo in the first 15 seconds of a game?

3) The opposing team is spy heavy. Fair enough I can protect myself and my stuff from a spy once i'm up an running. While it's annoying having a Sap on my sentry and being backstabbed less than a second later, it can be slightly avoided by not standing next to the gun... kinda hard when i'm trying to upgrade it. The real annoyance though, is when my entire team had run off somewhere, and i'm trying to shotgun 2/3 spys all by myself. Why is it that hardly anyone likes the idea of protecting an Engineer for the first part of a match?

4) Someone else changing to Engineer just before we start. I don't mind switching to another class, but on some maps having two engineers can be a waste of time, there's not enough ammo about. And switching just before I can is annoying. This is also extended to when I accept that the map is good with more than one engineer, and the other guy follows me to my obscure location...

5) Being shot by my own sentry. Fair enough I should probably move more, but when it's a level 3 one i'm trying to repair cos someone is shooting at it, then it swings round and kills me... bah.