Thanks for posting the video.
I like some of your 2hbh shots more than the your FH.
Few observations:
You hit a non traditional looking (to me), high arching, almost lobbing forehand that is a very safe shot but lacked an attackers stroke forehand. It was very consistent but like i said its very safe shot.
You need to work on better topspin forehand that can pressure your opponent more as this might work in some 3.5 matches but top 3.5s and 4.0 will crush you with your current fh stroke imo. The depth was very good but lacked pace or power and many guys like me will want to speed up the point and push you around more.
I saw that you often camped on the baseline mostly and you should work on setting up the point and moving into the court more or towards the net. I watched a few videos with 3 diff opponents and when you came to the NET ....remember to get low or bend your knees enough and i often watched you miss hit a make-able volley, i think it's more racket prep or taking your eyes off the ball. Watch some rafter videos or MAC vids on volleys.
Your 2hbh was decent but you didnt attack as much as i would like you to on that stroke, work on your angles, get a slice involved too to mix pace, spins and angles to work your opponent off the court or around the court more.
I saw you often hit right back to your opponent with both FH and BH. We are all guilty of this shot. Work the lines more or cross court angles to more your opponent out of position.
As for playing 4.0 level players , your going to really need to clean up your strokes and get a go to shot fot both sides, that means getting the forehand to generate more UEs and pressure your opponent. Serves are going to need a little more juice and placement as you want to let your opponent know my serves are tough and i can win on serve. Work on a good out wide and down the t serves, mix in some serve in volley in both your 1st and 2nd serve, come to NET more and if you hit better angles those shots will bring good rewards..in those easy points we love getting and put pressure them when your hitting with aggression.
Well...I dont have clean techniques either most of us dont. However, I do hit with an very western forehand but its heavy sometimes too heavy where i might hit the top of the net and not clear over the net. i like to play aggressive and my FH has some pop and much lower net clearance but i go for bigger shots, angles and love stealing someones pace.
I would work on hitting more aggressive returns too to really pressure your opponent to earn his service points.
Just my thoughts....