(1) Your toss location is very acceptable. Maybe you could benefit from tossing a tad more forward, but it's hard to tell from this angle. The major benefit of tossing further to your left as a right handed player is to be able to tilt your racket leftward and thereby gain a bit more topspin. From what I can see, you strike your first serve somewhat in line with your ear and that's just about where it should be struck, laterally speaking. You can also get a bit more under the ball (you jump a bit to your right to get under it) to hide a kick serve with that same toss location. If you send the ball further right, even if you manage to hit pretty decent flat serves, any attempt to introduce variety in your first serves will be betrayed by a very unusual toss.
(2) There is no need to toss higher. It is hard to tell exactly how you serve with this video because the motion is blurred, but I can see that you get a nice racket drop and get to the ball in time with a full motion despite the low toss. Not everybody is forced to have an extreme hand delay like Sampras! If you toss lower, you have less of a delay in your hitting arm; if you toss higher, you need a greater delay between the rising of your hitting arm and your toss. After all, the principle that matters here is to make a proper contact and to go through your motion without stopping -- if you can manage a lower toss, go ahead.
(3) If you are going to serve and volley, you need to learn to use your service as a means to initiate your run towards the net. You perform a serve and volley around 0:07, 0:29, 0:41, 0:46 and 1:00. In every instance, you hit your serve, land on the opposite foot (up to this point, it's perfectly okay), but you stop yourself and only then do you start running. Normally, if you take a snapshot of a server-volleyer right out of his serve, he looks like a sprinter:
Pete Sampras looks like that off a flat serve, a slice serve, a kick serve and everything in between. He lands all his serves in an athletic running posture and uses his serve to help initiate his forward movement. At the moment, your serve speed and your opponent do not trouble you much, but at some point that wasted step will be a major bummer. Fortunately, it's not tough to fix: you just need to lean forward a bit around contact and bother to land in a sufficiently balanced way that you can actually use that forward fall to start running.
(4) As you noted, you needto split step, especially on the return of serve. You were lucky enough your opponent did not notice this, but if you simply rush the net you are opened to be wrong footed or lobbed all the time... So, when the man in front of you makes contact, you split step everytime. Beware, though: a split step for a serve and volley play is not static. You still move forward during your split step when you attack the net off your serve.
(5) People mistakenly think that a good serve for this sort of tactic needs to be fast when, actually, the opposite is true. The real killer in the serve and volley tactic is not your serve, but your court position. Your serve is an approach shot of sorts: the goal is to give yourself easier volleys, not to hit aces. The reason this tactic can be so deadly is that
from the service line and onwards you can easily play insane angles. As such, you should privilege a serve that allows you to move further into the court before having to hit your first volley. In this video, you strike most of your first serves as flat serves and that runs counter to what the vast majority of the best serve and volley players have been doing since decades -- and did so for a good reason. It's better for a serve and volley player to privilege putting more action on the ball and to keep his first serve percentage higher than to try to rack up digits on a radar gun: it gives you a better court position to hit your first volley, it still troubles your opponents a lot, and it forces your opponent to face more situations where you can afford to miss.
(6) Your major advantage at the net is that you "see a lot of court." Again, exploit your forward position to angle the ball. You don't need big punching volleys: if the ball is above the net and you're inside the service box, just lay the ball at an angle and the point likely will be over.
Just to be clear, there are lots of things you do well in that video. You vary your serve placement, you hit nice kick serves, you do not try to do too much with your volleys (especially high volleys which can be tricky) or your passing shots, etc. It's just that you need to work on some aspects of your game to make it better still. By the way, if you want inspiration for volleying and executing serve and volley, watch doubles players. They tend to be leaps and bounds ahead of singles players in this department because they do it so much more often.
Finally, I'd like to ask you a question: are you a serve and volley player or did you simply tried to work on this tactic in this video? If you are one or intend on becoming one, welcome to the club!
