Your formation is more closer to 4-5V-1 than typical 4-3-3.
Strength would be rather strong in defence, with good potential to score via flanks against opponents with weak fullbacks.
Weakness is lack of grip in midfield and could be overrun by 3 MCs or ML/MC/MR, and could lose the match solely via conceding too much possession even when the team has a good quality advantage. Or being beaten by quality opponents in a 4-3W-3W via both flanks.
Perfect counter:
Opponents of 10% or better: 4-3W-3W or 4-3M-2W-1 via both flanks
Opponents of 10%- to 20%+: 4-1-3M-1W-1 via 1 flank. DMC position depends on if opponent ST quality requires 3v1 marking or 2 MCs need DMC help covering