I was in your shoes several years ago, looking at an aluminum jon/smaller motor/beater more or less typical 'first' boat. it really is a beginner stage, and I found out quickly that it's a short learning curve no matter what boat you buy. Luckily I found a full sized glass boat with a bigger engine on the back for a stupid low price, people cant even tell its older until I tell them it is, I bypassed the beginner stage and took it cautiously until I was comfortable, which seemed like no time at all. It came with a strong 101lb trolling motor on it so I was able to explorer more water before it hit shallows.
Since you're mooring and you choices are similar to a Crestliner 1756 retriever, you might be able to find a decent used tracker 175 txw for relatively cheap. It'll have more room to expand and get more mileage out of it until you move on.
If you have any questions about maint., docking, nav etc shoot me a pm.