[What are the benefits of leveled up scientists and engineers?]

I have a related question, when do you really need an engineer? The pilot is almost necessary, the scientist is useful, but the engineer seems extremely situational and pretty much optional except maybe in hard mode when you don't have do-overs.

[Getting the Wheesley to higher altitude]

So I ended up going with the symmetrical thud rockets. Jeb couldn't handle the single rocket solution. Very similar to what Wanderfound posted above. Fly to the destination, point up and ignite the rockets.

[What are the most important things you've learned about playing KSP to pass on?]

I learned that the Wheesley jet engine has an absolute ceiling of 13000 meters, so don't take contracts above that altitude unless you can fit rockets into your plan.

[Evaluating contracts]

I am finding myself spending a lot of money trying to do some of these contracts. Since I'm learning, I have a lot of failures. My question is, are some of these contracts just impossible for a given tech level? My stubbornness would have me try and try in order to redeem at least some of the sunk costs and gain knowledge, but maybe I should give up earlier than I do if I'm chasing impossible goals.

Are there any 'rules of thumb' you use to filter out contracts?

[Getting the Wheesley to higher altitude]

No amount of intakes will help you anymore, that's a thing of the past. The Wheesley doesn't lose thrust because it has not enough IntakeAir, the Wheesley loses thrust because it's defined to do so.

That's very good to know. There are many bits on the internet about added more air intakes. I wish I had known before taking the contract however.

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I have one more related question. Another issue I have with the radial rocket is the center of thrust will be a bit high, I suppose I need to angle it a bit so that it points away from my CoM? Can I do that in the hangar? Putting a symmetrical pair of rockets on there will certainly burn up my fuel a lot faster. Also, how do I change the prefix of this post to [Answered]?

[Automatic Contracts?]

Actually a few more should probably be automatic. There are a few important ones at the beginning that will cause you to miss out on important science points if you forget to take them. I missed out on the leave the atmosphere one, just because I thought I had selected it but didn't.

[Getting the Wheesley to higher altitude]

most people have done it by attaching rockets to their planes. (the radial 'Thud' rocket works rather well for this if you have it)

That was going to be my next try actually. My concern is burning through my fuel slow enough to complete my missions. In my limited experience, rockets don't last long.

[Getting the Wheesley to higher altitude]

A lot of my nav targets in contracts are fairly high altitude (~17000+), and I could probably do them with rockets but a reusable plane would be better. I have been stubbornly trying and failing to exceed 13000 meters with my only jet engine, which so far is the Wheesley. I've tried large wing surfaces and 6 intake scoops (I only have the earliest one) but nothing has worked so far.

It's hard to tell when you're learning what contracts are actually feasable with your current resources. I'm finding that a lot of them require specially made craft which lowers the benefit of such contracts quite a bit sometimes.