What line should I grind next?

I’ve had my account since 2013 and have always played off and on but just started about 2 weeks ago again after a year (I know, I know, I was out why did I come crawling back). I am just about finished with the leopard PTA for the leopard 1 and have had a blast with this line. I’m also almost just 40k away from the VZ.55. I would definitely say I enjoy the gameplay for medium and light tanks the most and the adaptability they have to offer.

Here’s a quick breakdown of where I’m at tech tree wise.

America – T20, T29, T49

Russia – T34, Obj. 277, LTTB

German – Leopard PTA, Tiger 2, tier 7 on the light line (spaced the tank name), St Emil

Britain – Cromwell

France – AMX 12t, AMD 178B

China – Type T-34

Japan – Chi-To

Poland – None

Sweden – None

Italy – P.43 Bis

Czech – Vz. 51

Sorry for the long post but all suggestions and opinions are appreciated!