Only 1 is relevant. TC rises from +1 to +5 because many small cards were just played. You can assume the rest of deck contains more face cards than average thus you place big bets.
About 2, 3 and 4, they are really irrelevant for such small samples, last seven rounds. You really cannot see the randomness just by looking at the seven rounds. Also regarding 4, your last round win or loss, should not affect your bet size.
That being said, you can get the sense of the randomness after one or two hours playing. What you are looking for is if the casino is cheating by replacing some ranks of cards with other ranks of cards. The most common practices are replacing rank of six with rank of five (and/or four). If decks contains more fives and less sixes, dealer won't bust often. All night you will get much more often pairs of five, if you double and often get the third five, you need to be alerted. There is one BJ author named bjanalyst who invented a side card count called 5m6c (5 minus 6 count) which is very helpful in deciding if the casino cheats using this practice. Basically set the 5m6c side count initial value is zero. If you see a six card, you subtract 1. If you see a five card, you add 1 to the side count. If the side count are always positive in almost every shoe after playing one hour or two hours, you can conclude the six decks contains more five cards than six cards. People use only HiLo or Zen cannot detect it, but people using 5m6c side count can. Casino cheat using this because TC fluctuates as usual, but dealer makes his hands in most of hands. At nights that dealer seems never bust, player needs to consider this possibility. And 5m6 side count is the tool to use. Another similar cheat is to replace eight and nine cards with face cards. This will affect TC. It will make TC stay negative all night thus AP never got the chance to place big bets. The tool for detecting this is to use 8/9 side count. If the number (6D should have 48 such mid-cards, if playing 5/6D, you should reach 40 in the end of the shoe.) constantly end below 40 and TC always stays negative, consider the possibly of this cheat. This also affect your index play on 12 v 2 and 12 v 3. You will often get a face card even TC is negative. After one or two hours, you will get the sense that something is not right. Why you bust often on such plays. But again, you cannot get the sense of these after only playing seven hands, I think one or two hours is required.