I hope this post isnt a bit redundant but im planning on going solo, minimal backpacking in Europe this summer starting from the 24th of july to the 4th of september.

Im Canadian and ill be from leaving Tel Aviv, Israel, so the ticket wont be too expensive, i hope…

budget is 4-5kUSD,

What am i looking for?
NATURE: im an outdoors person, im very active, hence cinque terre and interlaken, and im sure there will be lots more everywhere else
DRINKS: Im not gonna lie i wanna party, but i plan on drinking at the hostel prior to barhopping/clubbing
FOOD: I am gonna go to a restaurant here and there, but i love street food and i have great cooking abilities, which i plan on using at hostel, cutting costs by shopping at the super, bonding etc.
SIGHTS: Im a polisci history student so yeah, i wanna see some sights, ive been on many free tours and they were great

BUT MAINLY… im just looking for a good degree of spontaneity, seeing the world, meeting new people, and just going with the flow, having good vibes!

my main strategy for cutting transport costs is getting Eurail month pass trying to travel at night and sleeping on the trains as much as i can, i also took into account that most of the days in each destination may include half days leaving and coming into that specific destination, the itinerary is TLV to:

CROATIA
Dubrovnik for a day chill
-Hvar for 2 days
-Brac for 2 days
-Pag for 2 days
Split for a day

*train to BUDAPEST for 4 days

*train to Prague for 4 days
-Cesky Krumlov trip somewhere in there

*train to Venice for 3 days (maybe too many days?)

*train to Florence for 2 days
-half day at Piza
-off to Cinque Terre for 3 days then back to Florence

*train to INTERLAKEN for 4 days,

SPAIN *from Interlaken i dont know if i should take a train or fly to
-Barcelona for 4 days
-Valencia for maybe a half day but right away to Ibiza for 4 days (yes i know it will be expensive)
-Bunol for La Tomatina for 4 days
-Valencia for 4 days and then back to Tel Aviv

Questions:

Is starting at Dubrovnik better, or should i start somewhere else?
Is this feasible with train only, or should i fly in some cases?
Any Treasures i can fit into on the way, i know there a good distance from interlaken to barca?

Feel free to comment, Thanks