First of all, there is both good and bad when the charging is supplied by your 12V converter to both batteries. The up side is the fact that you don't need to worry about the batteries going down, but the negative is that you converter is usually set to about 12.5V which never fully charges the batteries. It requires more than 14V to get the batteries to full charge. A deep cycle battery is not as much effected by this effect as is the typical starting battery. For that reason it isn't a serious problem for most RV owners, unless the do extended periods of dry camping. For the starting battery it is more serious, but it still isn't completely problematic, particularly if you drive your RV frequently enough. Allowing it to sit for very long periods with a float of 12.5V for long periods will have some shortening of the battery life, but it is difficult to know how much and the frequency of driving the rig will play a part in that issue.
If you have one of the intelligent systems, such as the one from Inteletec, it does not float the 12.5V constantly either but only when the battery voltage falls so that will also tend to mitigate the negative effect. The converter does not supply enough voltage to ever over charge the batteries, but it may boil water from the electrolyte over time, requiring that you add distilled water.
It is very normal for the leveling jacks and any power awning to be supplied by the chassis battery since they must have power in order to retract before you travel and may need to operate when the coach battery is discharged. I don't have experience with the power awnings, but properly wired electric steps from the Kwikee company are able to get normal power from the coach battery, but if the key is switched to start the engine, it too will then draw power from the chassis battery if the coach battery does not supply power. Since jacks are not normally changed once you are parked, they are not a serious power drain.